I make stories up in my head, is it normal?

Hmmmm, okay. So, I'm in my room, and I start making up stories in my head. This also only happens when I'm listening to music or when I'm in bed. I don't just stand there and come up with it out of nothing, so I guess it's not that bad. But I'm kind of worried because I'm not sure if it is normal. I mean, I come up with stories about me and my friends and stuff that could happen. Like cool stuff. I DO REALISE, it's not real! Just to mention, I do it for fun. But I do it pretty much everyday, when I'm not busy. It doesn't bother me that much though. Oh, and I even end up crying in some of the stories I make up. That's stupid, but it's my fault. I've got to stop making up bad ones. I just wanted to know if I have a problem or if it's normal to make up these stories? :) Thanks a lot to whoever helps. xx