Boyfriend wants to try Anal

My boyfriend and I have been together for almost a year. We are very sexually active and try new things sometimes. One of the things we said we would never do is anal. Now a few days ago he started saying that he wants to try it. Once he accidentally put it in but barley & I was in so much pain and started bleeding. Maybe I am traumatized from that incident, but I don’t know if I should try it or not. Any advice ?