I am not going to force my son to accept my apology, but he doesn't need to be an asshole.
Did he do something wrong after accepting an apology?
Yea, and I am pretty upset with him.
I can understand being mad where someone hurts you multiple times.  You should find a way beyond apologies to come to a mutual understanding.
I'm just bullying him while he's in a weak state. He won't do it again.
You shouldn't bully someone to get them to do what you want them to do. This will just teach them bad behaviors and they won't respect you for going this. Would you respect someone who forced you to do something?