What is it about my videos that makes everyone think I have some disorder?

As long as this is not something you visualize yourself doing in real life or have thoughts of hurting anyone, I don't see anything wrong with it. What exactly do you want people's reactions to be? I could see why people would think your videos are "creepy", but isn't that the point? If you really just do this for fun and you say you're young, I think you might have quite a talent. Not sure how old you are but I think you should look into exploring it as a talent if it's something that comes easy to you. Not everyone might like it but focus on the big picture here... You should consider yourself fortunate to have the imagination and ability to create such cool work, and who knows, you might be the next Stephen King ;)