Man I have had the same experiences lately. I feel on top of the world at first then I start to think about how stupid things in life are and how complicated everything is. I start to think about my future and what I am going to do. Its sort of depressing but it gives me a new outlook on life. One of the best ways to get rid of that feeling is to munch out, smoke more and think on the bright side of things, all those makes me feel on top of the world again lol.