A childhood belief about skin

When i was about 6, I believed that when you streach your arms up, (and then you streach too hard and you get a sting in your armpit) that my skin had ripped right open. I always ran to the bathroom adn put a band-aid on my armpit. I never looked at it because I was afraid of blood. My mother would always see me with bandages in my armpits and asked me why. I would always say "because i ripped open again".