My FWB spent the night last night. We haven't had sex in a little over a month. Well, last night we had some make up sex (we got into a big argument a week prior & weren't on speaking terms) and last night when we were doing the dirty I could feel a weird popping inside & we could hear it. I don't think it was my IUD, he said it didn't feel like it. He thought it was just my wall or my body adjusting to him again after a long time away.