I work in a vets office as a vet tech and unless there is someone there all night there is no reason for your baby to stay overnight. I would insist on bringing my pet home the same day. He is better off at home with you than in an empty vet office! Also we rarely ever give males pain meds after neutering. The little pain theu feel only helps, as they will not be too active and that's what we want after surgery! Even the females usually don't need meds unless there was something unusual about the spay or if they have something else done like some here did, teeth etc. Again because if they experience a little pain they will stay more calm than if they don't feel any pain. Does any of this make sense? I hope I explained it right .