Is it normal to imagine excessively and talk to oneself?

Hello doctor,

I talk to myself. I have done it for as long as I can remember, I called on my other worlds, and I play different people I make up their lives in their personalities, friends, and stuff. I run it like a movie, and I play one character make and the rest I react to. And will talk to me out loud and walk around and pick up imagery objects and makeup settings, like a movie.

Last year I was in a mental hospital for a suicide attempt and cutting and stuff. And in there you do not get phones and stuff, so I was in my world a lot, but for once I was playing multiple worlds at the same time. When I am not alone, I play in my head. I still can function and get good grades and school, but I do not have friends I play in my world.

I guess it started when I was 8 it bullied, and I liked my other worlds better, and other stuff happened to me. They call it trauma or whatever. But anyway you could say I got better. I play myself in my worlds with a different personality and world. The only thing staying the same is my name. But I am worried because I am 13 but do it in secret. But my brother is 9 but acts like 5 and doses it in the open. He is loud and runs around talking to himself, and my family thinks he needs to play a sport. So I am asking if this is normal or something or just another reason I am crazy.