I'm 14 and feel i'm losing my "childish innocence" but i don't want to?

I was exactly the same as you when I was a child, i'd get lost in different worlds with my imagination. I think growing up you do loose that innocence and it does make it harder to go back to those days of day dreaming. But that is a part of life and everyone grows up. Even great authors like J. K Rowling and C. S Lewis grew up but they always had that pion to write. I don't get much time to get lost in my imagination much anymore (I'm 25), but I always make time for a favorite book (Eragon, Eldest, Chronicles of Narnia). Anything Fantasy! So don't get discouraged with growing up, embrace it, you will always have your imagination!