WHat should i do? im getting abused?

ok so yea this is gonna be to the point. i emailed my princaple im getting abused by my mother she said to talk to her but i dont know wht the result will be. my mom abuses me a lot. she hits me on the head with stuff she blames everything on me I SWEAR!! even if its someone elses fsuilt. i just dont know how to explain to u all but its just.... abuse. she loves me sorta but she abuses me. she compares me to my brothers (older) and my sister (younger) when im obvously more studoius and when they do something bad oh nothing happens. i swear she abuses me a lot. i never went to y freinds house. i never went out with friends im 12 and today my mom threw me outta the house for saying to my dad she deosnt deserved to ay sorry to. so i run down the steps my dad was going out with mom when he made me go back in. but i said if shes in the same house as me ill leave. i called her a donkey and stuff. and i admit a talk back but she makes me. and she says at times its my dads fault for me having a tounge that talks back. and please dont say talk to her. i dont know wht to do. i rlly dont. and theres so much more she does