Boyfriend seeking others attention

So I've (20) been seing this guy (19) for a bit more than 2 months but I'm starting to have second thoughts about him. The problem lies in how his personality almost completely changes when he goes out to party. He likes to dance a bit too close with random strangers and one night when he got particularly drunk he like made out with whoever was nearby. How do I approach him about this or should I just leave him? The fact that he seeks others attention so much is really hurting me. I'd love some advice from someone more experienced as this is my first relationship. Thank you for reading