I once heard someone describe your twenties as "the lost years". Now, I'm no expert considering I am only 27, but I'm going to have to wholeheartedly disagree.
I don't think your twenties are about being lost at all. I think they are about finding out who you are and figuring out how to forge a path to get to where you want to be. The word lost implies that there is laid out path to follow or a correct way to go. The word lost implies that you have no direction.
In my experience, I have had tons of directions, but in many cases, I lacked the courage to take the first step. Courage to take a leap over that obstacle. Courage to keep going even when all you want to do is turn around. Your destination may change, and chances are you'll go around in circles from time to time. Don't let the journey discourage you. Don't stop looking forward. If you happen to be in one of those valleys, have faith that the view from the top will be worth the struggles of the climb.
Find your path, or forge a new one. Your life is yours to live!