I am a perpetual college student no longer in my 20s. I don't have to leave class a whole lot, but at least once during my three hour class. I finally recognized that I have a fear of not only people hearing my gut, but also of people seeing me leave for the bathroom. So what I've done is make myself go the bathroom one each class even if I don't necessary need to go urgently. It's made me get over thinking what other people think and it's allowed me to be confident that I can leave the room when the time is right.By the way, most of my classmates are younger than I, which seems to make it harder.