Should I have punched him?

I recently punched my "friend" in the jaw instinctively for shoving me into a random guy. He has also lied about me. And threatened to push me into quite attractive girls for what? His own entertainment and to revel in my humiliation? I've never done anything to him. I've thought about knocking sence into him, but I just did nothing. This was in 8th grade and he was not particularly big or threatening in any way. Although he was universally well hated.