ANAL HELP😭🙏🏻

My boyfriend and I want to try anal but I'm TERRIFIED😭

Ive got a finger up my butt and my ass eaten plenty of times but this is so scary to me 😭

I have IBS and I'm only gonna do it if Im free from flare ups for a week or so. I also have pretty chronic constipation :/ that's why I'm so scared.

Any tips or stories?? Literally anything will help