some pups don't bother, other cry a bit. Echo was a squealed where as delta didn't even seem to know something happened.
don't worry if he goes quiet later, it can make them a little lethargic, give him 24 House and you will have your normal puppy back. give the back of the neck a rub/massage to help the vacc disperse, this seems to speed up them going back to normal. or that what i found anyway.
Delta was very shivery. and a bit whinie when she got home just wanted to sleep. but they do perk up so don't panic.