Abuse

I been with my boyfriend for 6 years, yes he has put his hands on me , he left me a purple eye before & broke my blood vessel after that time it was the last time he didnt do it again, yeah im stupid for staying with him. I'm 17 years old. Last night he punch me so many times in my head I felt like I was gonna die of a bad hits on my head. I kept praying because Honestly I thought I was gonna lose my life that night, I felt so beat. He hit my back the hardest he could , wouldnt stop hitting my head I kept covering my face so he would oucnh me hard on my head, and i was scared I felt like nothing, something inside of me shut down, i felt dead he kept talking bad about my mom. My mom has never done anything bad to me, that my mom was a dumb ass and things like that. So i Hit him and it just went all bad. I let him hit me more i k ept pappogizing to him for saying something back. Even tho i knew i did nothing wrong !! After it i calm him down and spend the night. We didnt do anything he try to tho he try to have sex but I kept saying no & he would get mad. Now im home. Im scared. I wannan leave him but I feel like if i do hes going to do something to me. 
My head hurts really really bad I dont know if i could have a n injury now from so many hard ounches .... I meed help.. I need an advicesz im literrly  typing all this crying..