I feel like I made a mistake

This is probably going to be a long post, and I'm not in the best mental place, but if you can bare with me, I could really use some help.

I got into an arguement with my boyfriend this morning because I woke up to an empty 12 pack of beer scattered across the kitchen counter. We aren't drinkers. I come from a line of alcoholics, and I will be sober for 3 years on the first myself. He knows how I feel about drinking. I can deal with a few drinks here and there, but I don't want it in the house. He's agreed to this. I went to bed at 2am and he stayed up to play video games. Totally normal Saturday night for us. When I woke up and saw the kitchen, I was pissed. I went about my Sunday morning as usual. I make sausage, pancakes, oj for the little ones, and coffee for us. Once I had the table set, I went to wake him up for breakfast. He's hungover and doesn't want to get out of bed. I asked him if he's seriously not coming out for family breakfast because he decided to get drunk alone last night, knowing very well how I feel about it. He gets up, has breakfast. I'm still mad at this point. I told him i needed to get out of the house for a minute and that I was going to run up to the store. As soon as I got in the car he sends me a text saying, "don't fucking come home today". I sit there for a minute crying in the driveway. He comes out screaming about how I can't take his car, I don't deserve too. (My jeep is broken down) I tried to lock the doors but I didn't make it in time. He opens the door, grabs the keys from my hand. I had such a tight grip, that the keys ended up slicing my fingers. He goes inside, I follow. I asked him why he would tell me to leave, just to take the keys from me? Then grabbed me by my side's and threw me backwards. I grabbed my phone and ran outside crying. I called 911. It took them 10 minutes to get here. In that 10 minutes, he came outside, yelled at me some more. Told me that he wishes he could kill me. That I should just kill myself. That everything would be better if I was dead. That this was my fault. That if I wasn't such a fucking idiot, this wouldn't have happened. Cops show up and take our statements. They took pictures of my hands, face, back (apparently there's something there too, but i haven't looked yet), and both sides of my ribs. After filling out my statement, I was being consoled by one of the officers when I hear him start laughing (His super pissed demonic laugh) and then hear the clicking of the handcuffs. I didn't think they would arrest him without my say. I asked what was going on and I was told that he was being arrested. When there's physical evidence to domestic violence, the victim doesn't get a say.

He works at a school. He's going to be fired. I'm a SAHM. He made it very clear that by calling the cops, me and my children will "be on the streets".

Was i just supposed to sit there and let him beat on me in front of the kids?

My 7 year old (from a previous relationship) was crying about how she doesn't want Jason going to jail. The officer tried explaining to her that he hurt mommy, and that's not ok. Which just made her cry more. Once the officers left I just hugged my daughter and started sobbing, telling her how sorry I am. I called her dad and asked him to come pick her up. He could tell I was upset and came right over. My daughter's father and his pregnant girlfriend held me while I cried, and cried, and cried. A few minutes go by and they leave. I feel like I made a mistake. The closest family i have is my sister, 500 miles away. I have no friends. He ran them all off. I have no idea what just happened or what I'm supposed to do