You need to see your dentist. It can shift all your other teeth out of line, and if you can't clean it properly it can cause all kinds of issues.
I am 14 and I have a tooth growing on the roof of my gums. Should I be worried about this? In front of where the new tooth is growing I already have another tooth
I had the same exact thing except that my extra tooth was in front. I had it extracted when I was just a bit younger than you and everything is fine now. Don't freak out about it. Goofy stuff like that just happens.