Wow, I'd never be going back there! I'd also be putting my concerns in writing--to the vet, the BBB and whatever agency certifies vets in your area.

How long it takes for the drugs to wear off can vary a lot. One of my dogs takes several hours longer than it should, one of them wakes up fully alert and ready to play! I'd be concerned if you aren't seeing any progress in the next four to six hours.

I always let my dogs drink a little bit the night after surgery. I don't leave the full bowl down for them, but offer little drinks occasionally. If they seem alert and are acting normally, I'll feed them a small meal late in the evening.