Hello I am Dr. Joey. Thanks for trusting me to help you and your pet today. I am a licensed veterinarian with over 15 years of experience. I look forward to working with you.
This does sound concerning for Baba. Is she a cat that goes indoors and outdoors? I ask because the most common cause of this sign is an infection which occurred secondary to a cat fight (from a claw usually...often hard to find the wound). Or a bit by an insect/snake could also cause such swelling.
SHE HASNT BEEN OUTSIDE
More unusual to have occurred in an indoor only cat. Do you have other cats or is she an only child? A possible altercation with another cat is possible. It is highly unlikely to be a fracture from jumping/trauma being indoor only.
SHE DID GO OUT A COUPLE OF DAYS BEFORE THE INJURY
The real question is if this is something that can wait through the holiday weekend or if you should take her to be seen on emergency. If she is very painful, lethargic and/or not eating, or the swelling is rapdily increasing, then I highly recommend take her in to be seen today or tomorrow. If she is doing okay and is nursing normally (make sure that she is actually producing milk from her mammary glands) and eating/drinking well, then you could monitor and get her in on Tuesday. This is most likely a focal infeciton (cellulitis) and needs an antibiotic.
SHE IS DRINKING EATING AND PLAYING WITH THE KITTEN EVEN USING THE PAW TO PLAY BUT WONT WALK ON IT
Then, you could safely monitor for today and see if this is worsening. If you can take her rectal temperature at home, and this is over 103F, then she will need to be seen by an emergency vet. But as long as she is acting normally as you report, you can monitor until you can get her to be seen by her regular vet as soon as possible. If any worsening, then she needs to be seen earlier. This probably needs an antibiotic to improve (via injection or oral).
You are certainly welcome. If you have any further questions this weekend, I'll be available and you can always reply to this question.
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