We moved house a couple of months ago. My husband and I took our two cats to our new vet's on Thursday for their annual booster. Everything went fine. About 3 hours later, one of my cats didn't seem right. He ended up bringing up his breakfast and slept quite awhile after that. Just before 7pm, I was about to prepare food for the cats and my dogs, and noticed that Tommy was around, but then disappeared. When I found him, he'd been sick - he'd brought up blood! I arranged to meet the out-of-hours vet, who gave Tommy an antibiotic and an inflammatory injection. He said that sometimes pets can have a reaction (which I am aware of, but mine had never reacted to it)...then he said, "he's had a cat flu injection today" and then it hit me...I hadn't had my cats vaccinated for years for cat flu because they're indoor cats. I'd never thought to request they not get that injection, and the vet obviously didn't think to ask if I wanted them immunized against cat flu. I feel horrible because I feel responsible for making my baby ill. Good news is that he perked up a bit within about an hour of getting the antibiotic, but still hasn't eaten today - not even the scrambled eggs I made him for breakfast. I hope he continues to improve - the vet we went to yesterday is on-call all weekend, but hopefully we won't need to see him again.