Update - just got home from the vet. He doesn't have a fever, but his abdomen feels a little "doughy". The vet said she hates to waste my money on x-rays and bloodwork, so she said to keep a close eye on him. There's a vet on till 11pm and to call if there's any vomitting or diarrhea (which so far, there hasn't been.....in fact, he's downstairs eating some supper quite happily). I'm also supposed to call to update her tomorrow. She thinks he might have eaten something. Hopefully it was just some food he got into and not an elastic or something (which he could potentially find in one of my roommates very messy rooms, but Sammy has never been one for elastics and garbage etc....he's only even been interested in cat toys and food).
BTW Sammy's worst vet visit EVER!!!!
He always growls now at the vet, but this time did it so much she had trouble listening to his lungs. He hissed and made motions as though he was gonna bite (he wouldn't actually dare to, he knows he be in super big trouble and other than at the vet, he's always very tolerant, has never scratched (at least not on purpose) or bitten anyone). He threw a fit and rolled onto his back. He even hissed and took a swipe (didn't connect, of course) at a picture of a cat on the wall!!! Not a good sport at ALL. I'll keep you guys updated on his condition.