Septate hymen

When I was 16 my bf and me were having sex and it broke my hymen so now I’m left with a small string like piece of it. It doesn’t hurt and it doesn’t do anything it’s just there. Now I’m 18 and my bf doesn’t know it’s not a noticeable thing but idk how to tell him about it. I’m ready for us to yk start doing things but what if he gets freaked out or thinks it’s weird. I just need help telling him because idk how to word it or even start the conversation