Bully

Hi everyone! My son stood up to a class bully that's been messing with a peer he's known since PreK. It all began during recess when the bully body slammed my son's peer, my son did say he was called down to the APs office because of this. But there's been several incidents since that my son has told me about like the kid making fun of the others clothing and saying he wears the same jacket daily smh. On Halloween the bully brought in candy and was handing it out 'crazy' as my son says so the teacher told him she would hand it out for him, she gave the student that he bullies some candy and then the bully at dismissal told him he wanted it back. My son outside of the school told the bully he was being an "@$#OL€" and the bully replied back "I'm being an @$hole?! Eff you" I want to run up to the school tomorrow about this, am I over exaggerating or should I just email his teacher and have a call about it?