Be free to create. Enjoy the process without expectation and you will be surprised as to what comes forth!
A lot of times people who feel they are not artists express themselves when they feel brave enough, in a medium of choice. And then the outcome is complete frustration and the desire to never create again. When I taught art, I think the thing I tried to steer clear of, with the students, was their expectation that they would not produce a 'work of art.' My message was always the same to them: "You are unique, and everything you draw is from you. So each creation is special because it's you."
I remember some of the looks I got when I said it; like I was speaking a foreign language, but now I realize it was the look of my words sinking in. Nothing is worse than seeing one of your students in tears over an art project. Art class should be an enjoyable class, not one of depression and torture! So while we all don't possess the natural ability to draw technically correct, the field of art allows for a wide variety of the definition as to what is art. If you have a vision to create, then create. Pick your medium and go for it. And the more you experiment with it, the better you get. With that new found confidence comes more incredible creations until you truly become that artist that you never thought you could be!