Experienced and professional animal trainer provide their insights in answering this question :
A. It is difficult to be able to tell without a full imic examination or at least a picture. It might be that the two things are unrelated. The swelling could be due to either phantom pregnancy or season, the skin pigmentation might be normal for her breed or increased for hormonal imbalances.

How to Identify Common Pet Problems ?

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

The affected mammary gland may appear dark purple or black in color, as the tissues begin to die off due to overwhelming infection and decreased blood supply. Affected dogs may become lethargic, develop a fever, refuse to eat, or begin vomiting as the infection enters the bloodstream and they develop signs of sepsis.
After heat, the progesterone levels in a female dog`s body drops; after they were in heat, the hormone prolactin rises naturally, causing the mammary glands and nipples to swell. This natural rise of prolactin causes the nipples to swell even if she is not pregnant.
If you are petting your dog and you notice a lump along the mammary chain, please have your vet examine her. In intact female dogs you may notice lumps that come and go after the heat cycle. These are typically due to mammary gland hyperplasia (proliferation of normal mammary tissue).
Swollen nipples in dogs may be caused by: Mastitis. Mammary gland tumor. Normal heat cycles or pregnancy.
On some dogs you can observe the very earliest signs of yeast when it manifests as little black or brownish specs on the underbelly, around the genitals, or where the legs join the body. These often go unnoticed, being mistaken for dirt, flea specks or simply part of the ageing process.
The puppies sometimes will scratch the mother`s nipples or the nipples can become cracked. This can allow a bacterial infection to begin in the milk ducts. Dogs, females and males, can develop mastitis when not pregnant or nursing pups. If this is the case, your dog will need to see your veterinarian immediately.
Enlarged or Discolored Nipples

You may also notice your dog`s nipples turning a slightly darker red than normal, which would indicate an increase in blood flow. Later into the pregnancy, her nipples may occasionally leak milk, as well.

Signs a Female Is in Heat

Think of it as the doggie equivalent of PMS. Swollen nipples – Sometimes, but not always, the nipples and breasts will swell slightly. This can also be a sign of a phantom pregnancy, when a female may begin to show signs of being pregnant even if she`s not.

The more common signs of pseudo-pregnancy include mammary gland enlargement with or without the production of milk, lethargy, periodic vomiting, and fluid retention. Dogs with false pregnancy often have a decreased appetite but seldom appears to lose weight, likely due to the amount of excess fluid retained.
Mammary cancer is the most commonly diagnosed tumor in intact female dogs that are older than seven years of age. Male dogs rarely develop such a tumor.
The average survival time for mammary gland sarcomas of any kind is short, usually between 9 and 12 months. Inflammatory mammary gland tumors are highly aggressive and typically present as a rapidly growing tumor with ulceration, edema and erythema.
These modifications appear roughly two weeks after breeding. Increased blood flow in the region brought on by pregnancy-related hormone release causes nipple changes. Nipple changes are a reliable sign of pregnancy in dogs that you should constantly watch out for.
Mastitis is most common in dogs that have recently given birth, but can also occur in dogs that have never been pregnant. Unspayed female dogs may experience pseudopregnancy, or false pregnancy, in which they develop symptoms of pregnancy such as mammary development and lactation, without actually being pregnant.
Mastitis causes the mammary gland to become blocked, so milk cannot be released. The teat swells and becomes red and painful to the touch. Sometimes, pus or discolored milk may be released. It becomes increasingly difficult for mom to nurse her puppies because of the pain, so the whole pack suffers.
If you see the mother licking her nipples after nursing, then she is taking care of the nipple hygiene herself. If she is not licking the nipples after nursing, you can use a warm, clean, damp cloth to wipe down the area. This should feel good to the mother dog in addition to keeping her nipples clean.
In case of infectious mastitis, vets prescribe antibiotics. Antibiotics such as Clavamox or cephalexin are prescribed. If your vet prescribes these antibiotics, you should look for the side effects in your dog. Untreated mastitis can cause gangrene, abscesses, or lead to a septic shock.
When you`re dog isn`t pregnant, her nipples are relatively flat and small. They`re usually light pink and don`t stick out too much. Depending on your dog`s color and the thickness of its coat, you may not even see them! However, that all changes after she becomes pregnant.
On average, it takes 6-10 weeks for their nipples to completely shrink back after weaning the puppies. But some dogs can take up to a whole year for that to happen!
High levels of prolactin cause many of the symptoms of false pregnancy. Phantom pregnancy can also be caused by spaying your dog too soon after an estrus cycle. The removal of the ovaries changes hormone levels at a problematic time in your dog`s cycle — leading to the symptoms of false pregnancy.
How many times should a dog mate to get pregnant? Although a dog can get pregnant from one mating, most stud dog owners will recommend the dogs mate two (or even three times), usually 24 – 48 hours apart each time, but this may depend on whether a tie or a slip mating has been achieved.
Week Seven

You will notice your dog`s breast tissue is swollen, her nipples are prominent and dark, and you may notice colostrum, a cloudy fluid known as “first milk” leaking from her nipples. She may start to shed the hair from her belly. You may also be able to see and feel the fetuses move beneath her skin.

Dogs with inflammatory mammary carcinoma and mammary sarcomas have a poor prognosis, on the order of weeks to months. Early detection of tumors is key for long-term survival.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

Q. My Pug has black spots on her teats . The nipples are slightly swollen. What could this be?
ANSWER : A. It is difficult to be able to tell without a full imic examination or at least a picture. It might be that the two things are unrelated. The swelling could be due to either phantom pregnancy or season, the skin pigmentation might be normal for her breed or increased for hormonal imbalances.

Q. My dog ran away 3 days ago , he came back later and immediately threw up all his food. He hasn’t eaten and is still throwing up since then.
ANSWER : A. I’m really glad to hear your dog came back! If you dog is vomiting I would recommend having him examined by a veterinarian because his vomiting could be caused by a gastrointestinal disturbance. He could have eaten something that upset his stomach, including an intestinal parasite or he could have even consumed something toxic. It would helpful for a veterinarian to evaluate for any injuries he could have sustained while being out of the home and for any abnormalities that could be causing his sickness. Stress could also be playing a role in his stomach upset since he was out of the home for several days.

Q. My 5 month old dog woke up today very lethargic and not very hungry. His feces smells very bad and it has an orange colored mucus in it. only 5 lbs
ANSWER : A. This could be many things, however first I’d ask you (if we could talk) if your puppy is vaccinated against parvo? That’s a serious viral disease that produces very bad-smelling bloody diarrhea. If he’s not vaccinated against parvo, please take him in to see a vet right away.

Otherwise, if he is vaccinated against parvo, he could have intestinal parasites, he could have eaten something that’s upset his GI tract, or he could have a bacterial infection, for starters. The orange color you mentioned has me especially concerned – I’m worried it could be blood. Regardless – he’s not eating, and he’s lethargic, so he likely feels pretty awful. I recommend you take him to see a vet right away who can figure out what’s going on and treat it appropriately.

Read Full Q/A … : Causes of Blood in Dog Stool

Q. My dog has had dark red blood in stools for 2 days now . She found & ate a baby bird back in August , could that cause a problem now after so long
ANSWER : A. It seems pretty unlikely to me that the bird ingestion could have anything to do with the blood in the stool you’re seeing now. Depending on exactly how it looks, it could be a number of things. If the stool is normal and has blood on it, it could be an anal gland problem (infection, tumor) or a problem inside the rectum, like a mass. If she’s got diarrhea along with blood, she could have a bacterial or parasitic infection in her intestines, or she could have inflammatory bowel disease. I’d get this checked out as soon as possible.

Read Full Q/A … : Causes of Blood in Dog Stool

Q. My dog is bleeding out of rearend after
going to vet for a leg trouble the vet says
it is stres
ANSWER : A. It could be many things causing the problem. If it is an unneutered female it could be a season, if it is in the urine it could be a cystitis which could be set of by stress amongst other things. It could be from the anal glands or it could be from the lower intestinal tract. If it is the latter I would be careful what pain relief medication you are giving as some can cause bleeding in the GI tract such as meloxicam. I would recommend having a recheck with your vet to establish where the bleeding is coming from as some causes may require treatment or a change in current treatment.

Q. I have an apricot poodle. I’ve noticed the left side of his nose has a black spot and is swollen. It opened and puss oozed out. What could be the caus
ANSWER : A. This could be an infection or it could be a growth with has got infected. I advise you get a full check up by your vet, a small sample can be taken to identify the nature of the lump and to guide most appropriate treatment

Read Full Q/A … : chianti.ucsd.edu

Q. Senior cat, neck lesion, orangey blood, and black spots on skin when groomed. Started today.
ANSWER : A. What you’re seeing that you suspect to be orange blood could be infectious material. Pus can take on a variety of colors and can look bloody due to inflammation. I would suggest cleaning the area with a warm, damp paper towel and then dry it well. Try to prevent your cat from scratching at it and remove her collar if she is wearing one. Keep the area clean and dry until you can get her into the veterinary office. She will most likely need antibiotics to treat the lesion. The black spots could be a change in pigmentation or also associated with a skin condition. Your veterinarian will know best after a thorough examination.

Q. My toy Schnauzer has red ears and the top of her nose is red under her hair ,help can ya tell me what I can do or give her
ANSWER : A. This could possibly be hot spots or if she has been out in the sun, could also be a bit of a sunburn. If she is itching you could try hot spot treatment which can be found at most pet stores. If she begins losing hair, please take her to the vet to rule out mange.