Abusive? 😭

Today me and my boyfriend of a year got into a huge fight in the car. We argue often. He started driving like an ass. Told him when he wrecked and killed someone that was on him. Started driving even more like an idiot. Told him I was done and slid the corner into Walgreens with the E brake got out and started walking. I’d like to note I’m also almost 25 weeks with his daughter and it’s raining and freezing while he proceeded to drive like that. now I’m just sitting in a car. In a parking lot. By myself. Notttt really sure what to do. 🤷‍♀️ do I leave? Is this red flag behavior? We live with his grandparents so what do I tell them?