Young cats butthole is leaking and hurts

Question
We brought our 7 month old, female, spayed, cat to my mom's house for the weekend. There are two other cats there, they played the whole weeekend. It was all fine until when we left she was whining and meowing when we touched her butt.

We got home and we noticed her butthole is secreting clear/yellowish liquid. It is covering all her hair around her butt too. Usually her butthole is kind of pursed outwards but, now it looks flat.

She was eating normal adult cat food at my mom's place instead of her kitten food. (it was only for 2 days)Instead of city water she was drinking well water (underground well)again she is 7 months, female, spayed, weighs 7 pounds or so. Just started dripping today in the afternoon. We also called the vet and left a message asking about this but i doubt they won't tell us anything other than "bring her in for a check up"

Answer
Sounds like your kitty is having a really bad case of diarrhea from the sudden change in diet.
Anytime you take your kitty somewhere to stay ALWAYS bring her own food.
Eating something new like that will almost always bring on a good case of diarrhea.Her rectum hurts because of the liquid nature of her stool.

You can give her some soft, boiled white rice in her food for a few days and that will help but she may not want to eat it. Add some tuna water (from canned tuna) to the rice and that will help her want to eat it.

If her diarrhea continues for more than two days she WILL need to go in and see a vet.
Hopefully she is also vaccinated since she was spayed.