A childhood belief about general

My brother use to chase me around with a shark book and try to stuff this huge blown up picture of a shark in my face all of the time and I'd always scream and run away. I was terrified of the pool, always thinking that somehow magically a shark would come out and eat me, especially in the night time for some reason. I also thought, i don't know where this even came from, that military helicopters would fly over my pool and drop "testing" sharks in my pool for some reason. And sometimes I would take late night showers, and I could never be in the shower at 12 o clock because I always thought that a shark would bust through the wall at that exact time with tsunami water and get me.