Obviously not the same situation as I had...lol She was a senior

The thing is a aint a punk ass I'll fuxk I niggah up

Well, you choose whether or not to make idiotic/unjustified decisions. There was probably many ways out of this situation but you chose to take the incorrect route; which led to the inevitable. If you wanted to enjoy freedom like everyone else, you should have either been the bigger man, or wait until AFTER SCHOOL to handle your business. But even then, you should still look at the odds of what consequences could be brought upon you after the incident.

If you simply fought him because of something stupid, and/or you were bullying him; count yourself done. If it was truly Self-Defense then you might be in the clear. But like Cryptic Soldier said, going as far as Self-Defense would be the best way to go about things because this is actually becoming a pretty big issue, in schools especially with bullying and suicidal activities going on more frequently. Make sure if you lie, you remember your story because the best way for them to catch you, is to catch you switching up your story. So come up with something that seems at least valid, and use it throughout the whole time because there is a huge chance that they may question you and the victim on the incident.

u fuk dat bitch up 1v1 no scope dat lil fuker

and I guess you're in middle school, right?