Well, put in these terms, probably no one of us has a purpose. Now I know that it is just easy to say but hard to do, but you should think what you'd like to do, and do it.
But searching a purpose OUTSIDE of you means to disregard yourself... to stay and enjoy the day could be purpose enough.

By the way, I too have a problem to feel rewarded for OBJECTIVE achievements that anybody else recognizes. I'm praise-proof.