Experienced and professional animal trainer provide their insights in answering this question :
A. It can be caused by insect sting, foreign body in the feet ( that can be under the skin in space between fingers), some injury… Swelling can become visible after couple of hours or a day. See your vet to check what is going on.

How to Identify Common Pet Problems ?

Our sources include academic articles, blog posts, and personal essays from experienced pet care professionals :

Most puppy mouthing is normal behavior. However, some puppies bite out of fear or frustration, and this type of biting can signal problems with future aggression. Puppies sometimes have temper tantrums. Usually tantrums happen when you`re making a puppy do something he doesn`t like.
Pacing and circling in dogs can be activities in which dogs engage in order to perform some normal activities like urinating, defecating, sniffing and investigating, or they can be compulsive behaviors which are not normal. They may also be indicative of underlying pain or a neurological disease or canine dementia.
Your dog can get high in excitement seeing you back from work or after a few days. This emotion can lead to them running in circles as a display of affection towards their owners.
Mouthing and play biting is a common phase for most pups and I often reassure owners that their pet will almost always grow out of it when they`re around three to five months old. Biting is also part of the natural teething process – this normally lasts until your pup is around seven months of age.
Be aware that even doing everything right, this behavior may not go away entirely until 5-6 months of age. Remember, this is a normal developmental period in puppies. For extra-bitey puppies, or those that are biting after 5-6 months of age, this blog will help give you some additional tips and recommendations.
As with humans, exercise can be a great stress reducer. Physical activities like walking or playing fetch help both you and your dog release tension. It is also good to provide your dog with a safe place in the home where he can escape anxious situations. Everybody enjoys a calm place to retreat.
Dogs have several reasons for staring at their owners, like to communicate with and understand us. Some dogs stare to manipulate owners, as in with begging for food or asking to be let outside. Training and dog sports are good ways to turn focused staring behavior into a positive experience.
Turning in circles before lying down is an act of self-preservation in that the dog may innately know that he needs to position himself in a certain way to ward off an attack in the wild.
For some love-their-people dogs, the sight of their favorite person walking in the door after being at work or returning from a vacation, puts them in tail spins– literally. They display their excitement by spinning quickly, prancing up and down — and some even let out happy, greeting yelps.
As with other dog behaviors, there can be several reasons that lead dogs to lick or chew their paws. These include injuries; skin problems; environmental, parasite, or food allergies; and boredom or anxiety.
Your dog may be biting because they are brimming with excitement and energy. Australian Cattle Dogs do need a generous walk each day. So start taking them for a long walk and throwing things for them to fetch as you go. If they`re tired and sleeping, they won`t get worked up and start biting so easily.
Puppy discipline uses a combination of redirection, basic commands that reprimand in a firm but calm tone of voice, supervision, and positive reinforcement. Positive reinforcement: When puppies exhibit good behavior or correct bad behavior, reward them with verbal praise, petting, treats, or playtime.
If your puppy is teething, try freezing a rubber toy; the cold rubber will soothe their gums. As always, supervise your puppy so they don`t chew and swallow any pieces. Make items unpleasant to your dog. Furniture and other items can be coated with a taste deterrent (such as Bitter Apple®) to make them unappealing.
Puppies can play rough. Puppy play consists of chasing, pouncing, barking, growling and biting. Many pet owners mistake normal play behavior as aggression or laugh off behavior that is a warning sign for truly aggressive behavior.
The most important thing to remember is that for the vast majority of puppies, mouthing or play biting is a phase that they will typically grow out of once they reach between three and five months of age.
Adult dogs sleep longer at night than puppies do — usually between 60% and 80% of the hours between 8 p.m. and 8 a.m. depending on their surroundings and their owner`s schedule. However, daytime naps are still important for adult dogs, who may sleep for up to 37% of the day.
Obviously, his stronger sense of smell is useful, but it`s also because dogs can see movement and light in the dark, and other low-light situations, better than humans. They are assisted by the high number of light-sensitive rods within the retina of their eyes. Rods collect dim light, supporting better night vision.
Common signs of anxiety in dogs include:

Barking or howling when owner isn`t home. Panting and pacing (even when it`s not hot) Shivering. Running away and/or cowering in the corner of a house.

Stress signs to look for include whale eye (when dogs reveal the whites of their eyes), tucked ears, tucked tail, raised hackles, lip-licking, yawning, and panting. Your dog might also avoid eye contact or look away.
When dogs engage in high-energy activities, certain chemicals are released in their body that prepare the dog for fight or flight. These chemicals include cortisol, adrenaline, and norepinephrine. With these hormones coursing through their body, it`s very hard for the dog to settle down and relax.
Another study showed that dogs follow the gaze of a human if the human first establishes eye contact with the dog. “So the dog knows the gaze-shift is directed at them.”
Along with superior night vision, dogs have better motion visibility than humans have. However, because their retinas` contain only about one-tenth the concentration of cones (that humans have), dogs do not see colors as humans do. Dogs see like a color-blind human.
As it turns out, this circling practice is geared towards survival. “Turning in circles before lying down is an act of self-preservation in that the dog may innately know that he needs to position himself in a certain way to ward off an attack in the wild,” notes Dr. Buzhardt.
Many animal scientists think it`s a form of communication among dogs. Ground-scratching has been referred to as a composite signal that involves chemical and visual components of communication. The kicking motion is a visual display for other dogs and may help spread the scent of urine.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

Q. Got a blue heeler, she is 4 months,she keeps biting at feet but nothing on them or in them.keeps turning in circles,keeps pacing the floor.
ANSWER : A. It can be caused by insect sting, foreign body in the feet ( that can be under the skin in space between fingers), some injury… Swelling can become visible after couple of hours or a day. See your vet to check what is going on.

Read Full Q/A … : Aggressive Puppy

Q. I’m almost positive my dog is afraid of the dark! Every time I turn off the light she starts crying! Is there a way I can teach her not to be afraid
ANSWER : A. You may need to take things very slowly. First off, you should consider using a night light in the room you have your dog in. I have a night light in my room for my dog, even though I don’t feel the need to use one. You should have a handful of treats, and toss several of them to your dog. While your dog is eating the treats, shut off the light, and then turn it back on and toss several more treats to your dog. While your dog is eating the treats, turn off the light and count to three, then turn it back on. Toss several more treats to your dog, turn off the light and count to five. Turn the light back on, toss several more treats to your dog, shut off the light, count to four. Turn on the light, toss treats, turn off light, count to eight. Turn on light, toss treats, turn off light, count to five. The key is to randomly increase and decrease the amount of time the pup is in the dark. Work on it slowly, slowly build duration. Do not expect it to happen all in one session.

Q. My dog licks his feet and legs and they are turning brown. He is a white dog. Can you help?
ANSWER : A. Licking the feet and legs can be caused by a number of things in dogs including allergies, illness or even stress behaviors. Allergies are the most common in dogs, with yeast infections coming in second. Allergies can cause the area to become red and itching, making your dog want to lick and chew on them. Over time, the area may become stained from saliva, especially in lighter or white-coated dogs. Yeast infections are also common between the toes, and may cause a smelly “corn chip” smell to appear near your dog’s feet. Again, dogs will attempt to lick and chew to relieve the itch. Keeping the feet clean and dry can help relieve both allergies and infections and pet wipes or a baby wipe of all paws when your dog comes in from outdoors may also help. Keeping your dog from licking the space with either dog booties or an Elizabethan collar is also good as it will prevent secondary infection and staining of the paws and legs. If your dog is determined to keep licking and keeping the feet clean and dry do not help, then your vet can help by providing a medication to treat any infection or provide relief of allergies.

Q. How do I get my 10 wk old puppy to stop biting? He only bites me and my fiancé but licks everyone else. Tried bitter bite spray but he just barks.
ANSWER : A. When greeting your puppy, you should present an appropriate alternative for him to chew on. This can come in the form of toys. It’s normal for this age for puppies to be bitey. When you greet him, immediately offer a toy for him to chew on and calmly pet him. If he bites you instead, there are a few things you can try. You can yelp loudly startling him just as a sibling would do. You can freeze not jerking your hand away since that can likely become a game to him and you can also keep him secured in a play yard where if he bites, you can simply remove yourself from him so he learns all a attention goes away when he bites. Only give attention when he is calm.

Read Full Q/A … : Leerburg

Q. My dog is afraid of hard surface floors. How do I teach him to walk slowly on them so he won’t slip?
ANSWER : A. Start by putting down runners or rugs on the routes he usually takes. This will help him keep his grip better. Dog boots may help him keep better traction as well. If he is very high energy, lots of exercise and play will help him settle down and not be as active inside. Take him for lots of walks outside, teach him obedience, play fetch with him, anything and everything to get him to wear down that excitable edge that may be contributing to his hurry and slipping on the floors. Obedience training will also teach him to look to you for direction and enable him to listen better when you tell him to slow down. Keeping his nails trimmed short will also let him keep a better grip when walking on the floor.

Q. 2 month old Bulldog. While playing gets TOO rough:gripping hand REALLY tight/growling/shaking to the point of drawing blood. Aggresive?Normal?HELP!!
ANSWER : A. For the most part, this sounds pretty normal to me. English Bulldogs can be like this. What you can do is teach him bite inhibition. He needs to know that biting gets him nothing. Each and every time he nips, even gently, you immediately yelp like a puppy would, stand up, cross your arms, and ignore your puppy. Once he is ignoring you, go back to calmly playing with him WITH A TOY. Remember to always use a toy when playing with/petting/interacting with puppies. They will be teething very soon, and they don’t understand that biting you is inappropriate, so using a toy to redirect their attention is important. He needs SOMETHING to bite, or else he will choose your hand. Give him more options.

Another thing you can do is have a toy that YOU OWN. This can be a soft braided rope toy or something of the like. Dot not allow your dog to have this toy whenever he wants. This toy disappears when you are done playing with him with it, and reappears when you want to play. Never allow him to “win” games with this toy. Eventually, the toy will hold so much meaning, when he sees it, he will be instantly interested in the toy instead of your hands.

It also helps to have two bags of toys. Bag#1 is full of chew toys/rope toys/soft toys/etc. It comes out for one week, and then disappears and out comes Bag#2. Bag#2 has the same types of toys in it. This will keep the toys feeling like “new” to your pup and make him less likely to chew on you during play!

Q. When my dog wakes, he bites the first thing or person he sees
ANSWER : A. If your dog is startled easily upon waking and is biting people or objects, it is possible that he may have a vision or hearing problem, which causes people to startle him more easily. Making lots of noise before you approach (such as vibrating the floor or turning on a light) may help him to wake easier without startling, and may make him less prone to biting. It is a good idea to schedule a veterinary appointment to check for any health issues that could be causing this response.

If he is healthy and doing this behavior, or is acting aggressively toward others outside of waking up, then speaking with a local trainer or behaviorist in your area is best. Aggression is a hard behavior to train, and requires an expert in person to tailor training to your dog’s specific needs. Neutering may also decrease aggressive or dominant-type behaviors, however it does take times for the hormones to reduce and does not always solve the behavior.

If you are in the united states, you can find an animal behaviorist in your area by clicking this link: http://www.animalbehaviorsociety.org/web/applied-behavior-caab-directory.php

Q. I have a 8 month old Lab. He gets excited and likes to get mouthy and puts the persons hands in his mouth. Doesn’t bite hard. How can we stop this?
ANSWER : A. Bite inhibition is a great way to stop mouthiness that occurs often with teenaged dogs. There are several training techniques that can be done to help teach your dog how to play nicely! One is to teach a “Leave-it” command. Begin by holding a treat in your hand and asking your dog to “leave it”. If he attempts to chew or bite, a high-pitched YELP! will help. Once he backs away or ignores the treat, ask him to “take it” and offer it to him. Another useful way to teach bite inhibition is through the use of a tug toy. Again, the “take it” and “leave it” commands are used. During a tug session, ask your dog to “leave it” or “drop” and exchange with a treat. If he lets go of the toy, reward him! One final option is also “airplaning” treats. This method involves having your dog sit and then slowly lowering a treat toward him. If he goes for the treat, back away and start over. Once he can sit calmly and not chew on you, reward with the treat! All of these techniques are great for helping teach dogs bite inhibition. 🙂

Read Full Q/A … : Leerburg