I'm sick of this!!!

I dont really know where the best forum to post this would be, since i'm not on much, but here goes. So today I was in art class and as usual these kids that sit behind me started throwing things at me and yelling stuff that makes me shake from anger. I was trying to ignore it as usual since we were supposed to be working on the art project, which I otherwise enjoy. I just find it hard to focus sometimes regardless of them, but the make it harder. Anyway the teacher left the classroom and I saw my chance. I turned around and pushed the kid straight behind me back with his chair and screamed awful things. The worst i could think of at them. Then I got beat kinda and i was fighting with them, but i dont care about that. When the teacher came back in we weren't fighting anymore, but he noticed the bleeding (mostly from me ofc). They were "punished", obviously just for this sole incident. I just im sick of it. i hate it. i have no one to talk to. i just wanna harm myself again.