"You don't stop running because you get old, you get old because you stop running." - Christopher McDougall, "Born to Run: A Hidden Tribe, Superathletes, and the Greatest Race the World Has Never Seen"
Life's an adventure ... take it one step at a time and don't underestimate yourself! You're capable of more than you think you are! How do I know this? You're still here aren't you? That means you haven't given up!