I have had a few times that were what I would call more than uncomfortable. I was either in junior high or high school and in one particular class, there was always this girl who kept putting her feet on the back of my desk. I always acted as though this was overly annoying, but in reality I enjoyed it.
The male teacher (known to be perverted in his own right) was in front of the class gabbing on about whatever it was that we were "learning" about at the time. Still pretending to be annoyed by the girl's feet that were on my desk, I kept poking my pencil eraser down into the side of her shoe. She would giggle and put her foot down for a second and then teasingly put it back up again. This kept up until she let out a louder than normal giggle that caught the attention of the class and the teacher.
He was like: "What are you doing? Are you playing with her feet? Do you like FEET?"
I kinda just froze. I seriously remember my heart stopped beating for what felt like forever. I didn't answer him. I don't really remember what happened after that. Probably because my brain had no fresh blood supply from my still not working heart.
Another time, different seating arrangement, same teacher, same class, I was sitting behind a girl I was poking her rib with my trusty pencil eraser and eventually the same thing happened...but worse.
The teacher was like: "Are you tickling her? How would you like to be tickled? What if I had a bunch of these girls hold you down and tickle you on your feet? You had better behave or they might teach YOU a lesson!"
It was at this point that I knew I was going to die at an early age of heart failure. I again don't remember how that conversation ended, but it was never brought up by anyone again.