I can understand the desire to commit to one thing or another. Our society is designed around the concept that one commits oneself wholly to one thing or another. I think you should keep in mind, though, that our paths are not irrevocable - one can start writing at any point in one’s life. Other careers do tend to assume that one begins them at a younger age - but you can get off the track at any time. At any rate, I think you still have a couple of years at this point to find a path.