I had a kitten show up in my yard a couple of days ago. As I had appts. for kitten shots for two other kittens, I took this little guy along. The vet gave him a clean bill of health along with the other two and said all looked good. But, this little Siamese mix one seems to have a fever this afternoon. The vet said this sometimes happens with shots, just to keep an eye on him. He had distemper, feline leukemia, and dewormer. I take him back for the rest of his shots in 3-4 weeks. He just feels warm but has gotten up to be petted for a minute or two and lays back down. He has drunk water today, but doesn't seem to be too interested in food. Should I worry and how long should I wait before I insist the vet look at him again?