Gotcha. I'm not a mathematician, but your comment made me feel like I'm running out of time to make a difference, and I'm only 24. It also gave me a bit of confidence that I can. Anyway, better get to it!
Mathematics is good at making young people feel old.
Take Galois, for instance (http://en.wikipedia.org/wiki/Galois). Solved one of the major mathematical problems of his time. Founded a major branch of abstract algebra (seriously -- in a three quarter grad level course, you spend about a quarter on it).