If you are scared of the number 13 you have what I believe is called Triskadekaphobia. Its actually been disproven many times as to if it is unlucky. But there is always folklore.
As for another subject that was brought up, I agree with both Bryan and everyone else, the original poster did deserve an answer to his actual question. Then of course with the subject matter herein, especially with Friday the 13th just passed, it was gonna get of hand.