My boyfriend punched me?

Idk what to do. i was just with him today and i love him so much and he hit me. okay, first i walked all the way over from my house which is like 25 minutes away walking distance and he knows that!! weve been having some problems anyway, and he knows i have alot of guy friends, but everytime i talk to one he says, oh you stupid , i knew this would happen. or oh, why the **** are you talking to him? im gonna beat his ***. it's like, i cant have any friends!? ive known them longer than him. but i remember the old him and how cool he was about everything, i cant just dump him. but when i got to his house he was like, what took you so long? were you with a guy? and he was so angry that i was almost scared but i thought he would never do anything so i yelled, no! i was not with any guy! i came to see you! and he started yelling back in my face, full force screaming a bunch of swears and i finally just exploded and said wow **** you. and he just punched me. it hurt so so much, inside and outside. i never thought he would do anything. i started crying hysterically and he tried helping and i was bleeding and i just jumped up and ran towards his door and ran home, and he didnt chase me. he's been calling constantly and leaving me messages saying sorry and im just shaking violently. i dont want to go to school because he knows where to find me, but i dont want to tell the police because his mom has cancer in her lungs, bones, and brain, she has only a year left and the last thing she needs is her only son going off to jail. im so scared. help.