They say violence is not the answer to keep people in power safe (though it should obviously be the last resort as it can lead to an escalation of the problem as you have witnessed). Just know this girl won't kick your chair again and maybe she'll even learn not to bother other kids too. It's also a very good thing you learned this lesson now that you can get in trouble for violence as in the future the punishment for such actions are much much higher. Just make sure next time something like this happens, make sure you talk to the teacher or whoever your supervisor is (after telling them you will tell on them if they don't stop), so they at least know the situation and possibly even put a stop to it before you get physical.