Awkward Question

My bf recently expressed how he is open to trying anal and thinks he would very much enjoy it. He said he understands if I don't want to and won't push it. I told him I'd like to think about it.

I accidentally did it in the past 😂 (yeah ik how that sounds)

Ex was hitting it from the back, it slipped out and he shoved back in with force but in the wrong hole.

It was extremely painful and caused me to cry even tho it was one stoke.

It was very unexpected and shoved forcefully so i understand how that plays a part.

Does anyone have advice or tips? I'm open to new things and want to keep our sex life interesting but I don't want it to hurt badly.