Sneaking out of my bedroom to go say hi to my grandma. I had been grounded to my bedroom because my parents were mad at my grandma about something. I crossed the hallway anyway, then my parents caught me and spanked me until I was crying.

That, or when I was rubbing my forehead back and forth against the frame of my bed, because it was bumpy metal and had an interesting sensation, and I was so bored and ignored that this was the most fun I could have. My dad came in to find out what the noise was, then left. I, being very young, took this at face value, so I went back to doing it, only for him to come back in a minute later and yell at me to stop.

I can't remember which actually came first, but I'm pretty sure it was the top one.