When your feeling down, do you know you can change it, like that. Put on a beautiful piece of music, start singing, that will change your emotion - or think of something beautiful, think of a baby, maybe one you love, really keep that thought in your mind, block out everything but that thought. I guarantee you'll start to feel good.
Never underestimate the power of dreams and the influence of the human spirit. We are all the same in this notion: The potential for greatness lives within each of us.