Recently spayed female won't stop going in litterbox.

Hi, I'm going to try to get this cat to the vet as soon as I'm a le but I wanted to get some feedback.

I'm fostering an adult female cat and her 2 9 week old kittens, I had mom spayed on Thursday and was doing well up until yesterday. I found a very small amount of blood in the litterbox after she squatted, but then began noticing she was constantly using the litterbox, going in and out every minute, but to seemingly to result. I also found that she peed in a carrier I keep the in the bedroom, or I assume it was her, it could have been a kitten. She seemed to be recovering well, but now I'm unsure. She's isn't lethargic but you could barely tell because all she does is go in and out of the litterbox. Please give any advice or ideas of what could be happening.

Other factors; I have her seperated from the kittens in an extra large dog crate, her insicion looks like it's healing well, and they also vaccinated her even though I asked them not to as she had distemper and rabies 6 weeks ago. I have let her out of her crate under supervision, and thought she would be fine until I found the pee in the carrier. She also peed all over herself when I picked her up from the spay clinic. Today when I checked the litterbox it seemed as if she didn't pass anything.

It sounds like she could have a UTI, my cat Susy gets them occasionally and repeated trips to the litter box with no results are the first sign that her bladder problems are flaring up again.

Please take her to the vet as soon as you can. They need to establish the cause of the UTI. It could be anything from stress to diet changes to bacterial infection. They're usually treated with antibiotics, but there isn't much you can do apart from let the vet check her over.

Sounds like it could be a possible UTI.  I'd either bring a urine sample into the vet in the morning or make an appointment for her if they can get her in asap.  I doubt her urinating on herself after you picked her up for her spay would be related, that can happen after anesthesia.  May or may not be related to the spay, best thing to do would be to get her to the vet tomorrow.  

Okay, I basically just wanted to make sure I didn't need to immediatley run her to the local emergency vet, as the rescue doesn't have enough money for that. I'll take her to worn tomorrow as that's the best chance of her seeing a vet asap. Thank you got all your advice.