I need advice 😐

So. My boyfriend and I got home from a party before my parents and we started messing around. My mom has the find my friends app set up so he and I tracked her phone to see if they were gonna be home soon and it said they were still where the party was so we started having sex. We thought we were alone so we were relatively loud. After we finished I went to grab a towel from my nightstand where I normally keep them and there wasn’t one there. So without thinking I just threw on a shirt and nothing else and opened my bedroom door with my boyfriend butt naked to grab a towel from the bathroom and there my mom was in the doorway of her room. We made the most awkward eye contact and I freaked and came back in my room and slammed the door shut.

I’ve been having sex for over three years and I’ve never told my mom that I’m not a virgin. I don’t know if she 100% knows he and I were having sex, but I’m so embarrassed. Do I straight up tell her what we were doing? Or do I just pretend it never happened and not say anything?

I normally don’t wear underwear to bed so I mean she could assume that I was just getting up to pee; but my boyfriend was over and she knew he was. I’m just nervous