Bart, my ratty, has been biting in... er... areas he shouldn't have been lately. So, my stepmom told me to put him back in the cage every time he did that. Problem: What if we're teaching him to bite me there if he wants to go back in the cage? So today, he was on my shoulder, and it seemed like he was trying to nibble, so I squeezed his muzzle, then when my smart little guy figured out how to wiggle out, I let go, it was only for a few seconds, Two questions:
1. Does having his muzzle squeezed hurt Bart?
2. What should I do to get him to stop biting?

Thanks.