Well, I heard once that a police officer accidentally locked himself in the bathroom stall at the station. His partner was outside laughing so hard while he was trying to figure out how to get out. After a while, they had to call the maintenance guy to unlock it.
I was at a new job and still getting used to the office layout. I thought I was going into an empty meeting room to use my phone privately. But it turned out it was the bathroom. I was just standing there on my phone when someone walked in. I quickly said 'Wrong room!' and scurried out, feeling so stupid.
In my high school bathroom, there was a group of girls who always used to sing really loudly in the stalls. It was like an impromptu concert every day. They would sing all kinds of popular songs and sometimes even make up their own lyrics. Everyone outside the stalls would be listening and laughing.
A colleague of mine went into the office bathroom. He thought he was alone and started singing at the top of his lungs. But then another guy came out of one of the stalls. My colleague was so embarrassed and ran out red - faced.
One time, I was in a public bathroom. As I was using the toilet, I heard a really strange noise coming from the drain. It sounded like something was trying to claw its way up. I got so scared that I quickly finished and ran out. When I told the janitor about it later, he just laughed and said it was probably just an old pipe making noise.
Once, I was in a public bathroom. I was in a hurry and didn't notice that the toilet paper roll was empty. When I realized it, I had to shout for help through the door. It was so embarrassing.
My cousin was taking a bath and had a bunch of bath toys in the tub. He was pretending to be a pirate and standing up in the tub. All of a sudden, he slipped and his toys went flying everywhere. He was okay but had soap in his eyes and was yelling for help. It was so funny seeing him all soapy and disoriented.
There was this other story where a family had a pet parrot. One day, while someone was in the bathroom, the parrot flew in through the window. The person was so startled that they jumped up, and then there was this hilarious chaos as they tried to shoo the parrot out while still maintaining some privacy. It took a good few minutes before the parrot finally left, and the person was left laughing at the absurdity of it all.
Once, my cat followed me into the bathroom and jumped into the bathtub while I was filling it up. It was so startled by the running water that it tried to climb out but slipped all over the place. It was hilarious to see it scrambling around with wet fur.
Once, I was in a bathroom stall at a concert venue. There was a girl in the next stall singing along to the music outside at the top of her lungs. It was so funny to hear her energetic performance while we were all just supposed to be using the bathroom.