I'm 13 and ever since my sister began to crack her fingers I think I've had a fear. It's not really cracking the knuckles it's more pulling the fingers out of the sockets. When ever I see anyone do it I with keep on cringing and shaking and a few times I've even yelled at the person doing it. I've also gotten so stressed when thinking about it that I cried. If anyone knows what this fear is please let me know?