Are you a born writer? Were you put on earth to be a painter, a scientist, an apostle of peace?
In the end the question can only be answered by action.
Do it or don't do it.
It may help to think of it this way. If you were meant to cure cancer or to write a symphony or crack cold fusion and you don't do it, you not only hurt yourself, even destroy yourself. You hurt your children. You hurt me. You hurt the planet.
You shame the angels who watch over you and you spite the Almighty, who created you and only you with your unique gifts, for the sole purpose of nudging the human race one millimeter farther along its path back to God.
Creative work is not a selfish act or a bid for attention on the part of the actor. It's a gift to the world and every being in it. Don't cheat us out of your contribution. Give us what you've got.
From "The War of Art" by Steven Pressfield