Should I have filed a police report for domestic violence in lieu of a contract for damages?

My ex & I got in a fight where he tried to break my neck twice 1ce after he scratched me and I punched him in the arm before I left the room to cool down & 1ce when he followed me to the bathroom 30 seconds later. He admitted in front of my friends that he should have "popped my neck off" when he had the chance. I couldn't call the police because one of the roomates has pot all over his room and I didn't want him to get in trouble too. He broke my phone when I went to call 911, stormed out, and came back crying. My friend let him back in while he found a way home to Memphis or Jacksonville. I gave him a contract for bills he said he'd pay me back for and my broken phone but I don't think he's going to pay up. I really want him be sorry & make things better by repaying me. What should I do?