Definition: In this task, you are given a Reddit post as a text. Your task is to generate a title for this text. The title should start with "TIFU by", followed by a situation that caused humor. The title should contain 7-12 words, ideally.
Input: Text: this actually happened when i was in primary school (i'm from the uk this means elementary). okay so school had finished and i was heading to the reception were i would wait to be collected by one of my parents because they were always late for one reason or another so i could never wait with the others kids. anyway back to the story, on my way to reception i have to pass through the schools gym/hall. at this point in my life i was curious about sex and would often just randomly start humping the air pretending i was having sex i guess? well this one time i was walking through to reception when i thought i was alone so i did my "thing" and started to hump the air, shortly to hear "that's a nice dance op" i turn around and it's my teacher, somehow i didn't hear her behind me, i didn't say anything but i'm sure my face resembled a baboons ass. it never did get any less awkward for me for the rest of my school year.

TIFU by humping the air whilst alone and not knowing my teacher was behind me.