USA, went to the vet already but looking for more advice
I brought home a new 5 y/o neutered male kitty to my existing one kitty household on Friday afternoon, so today is his fourth full day with me. He’s been separated in my bedroom and closet from the other kitty but I was doing some scent swapping. According to his records, he was having some episodes of diarrhea at the shelter and was put on an I/D diet but the shelter seemed to assume it was anxiety related and actually did not give me the correct food. The cat was also recently dewormed in the last week along with flea/tick meds. He tested negative for FIV and FELV in February.
The new kitty has been having one episode daily of loose stool (pudding consistency) with no visible mucus or blood, but it does smell BAD. He also had one episode of vomiting that was just food/hair. I got him to the vet today and got him back on the I/D diet but it turns out he also has a fever (103.9) even though he wasn’t presenting as symptomatic. I was under the assumption it was completely dietary related until I found out he has a fever and now I am stressing out really badly. I got a tube to collect a stool sample and will hopefully get those results this week but I’m terrified it’s going to be something bad, super expensive, or that my other kitty will also get sick. For now, he’s eating, drinking, playing fine, but any words of wisdom are appreciated. Could this still be entirely dietary related or stress?