It wasn’t prom, but I have a similar story that might or might not be just as bad.
Our first year of high school my class took a traditional week-long trip to Gettysburg in order to do the full historical tour. As a "reward" there was an 4-6 hour stop at Hershey Park on our way back, and everyone was allowed to group up so we could explore somewhat independently. Being 100% incontinent I did all the necessary prep, felt confident, and was ready for the roller coasters. Unfortunately, after a week of junk/hotel food, my stomach was pretty backed up, so the combination of high speeds and chocolate took quick effect. Following my group of friends, crush included, I felt agonizing cramps that gave me a ten second warning to duck into privacy and lose ALL control. When it was all over I was a total mess, and wound up having to have a friend flag down both my private nurse and the school nurse. They helped me to the nearest bathroom, cleared it, and locked it while they helped me clean up... Only for me to walk out first and learn that it was a Women’s Restroom and there was now a long line of girls waiting, including my classmates.
Whoooole lotta shame to live down after that one.