How can I make myself sleep in my own bed?

Okay, this is embarrassing, but I'm 15 years old and have never slept in my own bed. Well, I have, but only when other people have slept over. I usually sleep in my mom's bed with her. I know this is quite strange, but for some reason I just can't. It's partially because I'm afraid (not sure what of) and because I just feel comfortable in my mom's mattress next to her (since I have been doing it since I was a young child). How can I sleep in my own bed comfortably and without being afraid? And no, for some reason my mom has no problem with me being unable to sleep in my own room. I probably would if I were a parent.