For myself and other beginner writers, there's a self-doubt demon, conscious or unconscious, that telling us, "You're not really an artist. You're not really a writer. A writer is Hemingway, Yeats, Twain, Faulkner. You call yourself a writer? Ha! You're not in that class. Who are you trying to fool? Do something useful."
That self-doubt demon is evil. You have to confront him, punch him in the stomach, kick his teeth in. He's holding you back from doing what will make you happy. Of course you're an artist! Of course you're a writer! If you weren't, you wouldn't be trying to find time for it! Yes, you're not a Faulkner--yet; that's because you haven't put enough time in. And maybe you'll never be that good. So what? You're still a writer, you're still an artist. This is what you do.
A couple years ago, at Song School, I went to a class by Beth Nielsen-Chapman. She's been making a living as a songwriter in Nashville for 25-30 years. She said (paraphrasing), "Everyone has had unique experiences, and so everyone sees the world in a unique way. Therefore, only you can write your songs. No one else can." This had a huge impact on me. On the one hand, it means that the greatest songwriters--the ones that I admire the most--can't write my songs. Even with their craft and experience, they don't see things the way I see them. That's a powerful feeling. On the other hand, it's an awesome responsibility. It means that, if I don't write these songs, they will never be written.
Of course, the self-doubt demon is still there. Even after knocking him out, he gets back up and sucker-punches me when I'm least expecting it. It's a constant battle, but I think that half the battle is being aware of his existence, and knowing that he's wrong.