Am I the jerk for beating a woman because she has been bullying me?

I'm 11M for starters. So this started a few weeks back of the post. I went into school and tried to be social to people but this woman I will be calling Nancy didn't like that. For reference she is practically double my size. She is 11F. She hit me in the back with a HAIRBRUSH and said something like "Don't be so creepy next time." I knew I had a problem with Nancy.

So the next day I came into school and at break I went outside to just have some fresh air as you do. So my school had a little hill of grass and there is a massive Bush there and Nancy decided to get my gluestick and throw it in there.

I told my mum (I am English.) That Nancy had been attacking me over phone on maybe last Friday. So timeskip to the next week and she hurt me again and I had to mentally recover from her. So on Thursday I had a day off of school because I had literally had enough but I promised to my brother and mum that I'd fight back.

So lunch on Friday was it I went up to her got a giant looking stick but I was too scared. She was bigger and stronger than I could ever be. Also a guy snatched the stick so later on inside miss said to sit down but I didn't I shouted: "I WILL DO WHAT I SET OUT TO DO!!" So Nancy got up and went out of the room but I then chased her and beat her full of rage. Mind you she has been verbally and physically assaulting and abusing me for no reasons.

Sorry for the long story but I just needed a vent. Also I'm facing a suspension for having feelings☠️☠️☠️ End if post