Aspiring writer...? Advice please?

Hello, I'm 14 :) and since I was a young child I loved to write little short stories and such. Any of my English teachers that have read some of my creative work and my parents have told me that I was a good writer. It wasn't until recently, when I took up writing fanfictions, that I had ever considered becoming a writer. I just might want to become a writer, so does anyone have any advice for me? Thanks in advance :D