If you are content with the best you've done so far, you will never become the best you can be because your best can always improve and become the greatest.
If you always put limits on what you can do physical or anything else, it'll spread over into the rest of your life work, morality and your entire being.
Frustration, complication, and misery are available in abundance, but so is God's grace, No matter how things look, know that God is still in control. Stay in peace, knowing that He will always be with you."
At the end of life's journey, it's the HOW you spent youyr life in those years that counts. So do what you enjoy doing, do it right and live life to the fullest.