Oh, I love topics like these!
I was a junior in academy and on a mission trip with my school to Mexico. The bathrooms in the run-down building we were staying in didn't have doors, so we hung up blankets as make shift curtains. I was in one, about to do my business when the guy I just happened to have the biggest crush on walks in and sees me just as I was about to sit down.... At least he apologised for it. But I couldn't make eye contact with him for the rest of the school year.
Another time is when I was at the library with my parents, younger bro and younger sis. My bro and I always had this running joke where we'd pretend we didn't know eachother when we were in public. I thought I saw him standing at a table looking through some pamphlets and I approached him from behind and started saying stuff like "Ew, who are you? You're weird! I don't know you! Go away!" When I looked up, I saw it WASN'T HIM!!! I apologised, busted out laughing, and ran outside to the car. Needless to say, I never went back to that library again...