Have you ever observed how a single,insignificant thought can dominate yourentire day?Perhaps you recalled a morning chat andbegan to question if you had said the wrongthing. After a few minutes, you thoughtabout how the other person might haveunderstood what you had said. Before long,you were repeatedly going over theexchange, searching for errors that mightnot have even occurred.Or maybe you've been worrying aboutsomething that might happen tomorrow allnight long. Your thoughts dart betweenpotential outcomes, attempting to preparefor each one. Hours go by, but rather thanfeeling ready, you start out feeling morenervous.