I have also followed a similar trajectory to you. My early 20's I wanted to do something 'great'. But my ambition was what Paul identified in this post as the type that precedes experience. As a result, I became restless, agitated if I thought I wasn't pursuing the right things, competitive.

That is slowly disappearing from me, for the better. Now I just try to focus on doing things as well as I can. I don't worry about what to do, because really that will flow from your intuition. Just do what you want to do. Maybe it'll be great, maybe not, but you can't force greatness.