My dog is in a lot of pain after being neutered?

He may not be in pain, my cat walked odd for a few days and whined but was never in pain, it feels weird for him, he's missing things and he's probably not in pain but just uncomfortable, just keep spoiling him with treats and make sure he doesn't have to walk far for his food and water, if he doesn't want to lay down don't make him, just let him get used to the weird feeling he's having.