artistic self-doubt

Are all artists as neurotic as me? Almost every time I finish a new composition, I go from not liking it to deciding it's pretty good (though there are a few tunes I write that never really grow on me). Then I get paranoid that I'll never be able to compose another tune and the fear is paralyzing until I eventually force myself to attempt to write another tune, which involves being unsure of myself during the entire writing process. And then the cycle repeats itself all over again.