What should I do? I'm worried about my girlfriend.?

My girlfriend's dad was super mad. I mean really mad. He sped up at our school and did a hard brake and drove off after he picked her up. He's mad at something our vice principal said. We dont know what she said though . The biggest thing we've done was hold hands. Also our vice principal thinks that my girlfriend lies or doesnt respect her. We dont know what she told her parents, but there mad and said she was in trouble . Lastly my girlfriend told me that she wasnt allowed to date. I afraid for her because i think I heard her say her dad hit her once, and I'm really scared and I want her to be ok. What should I do?