If right now you felt too old and too underachieved, then you only had your past self to blame.
Nobody, not even God, was responsible for your condition today. Your past self chose and made who you were today.
So, be kind to your future self.
Make sure your future self is healthy, happy, blessed, balanced, and whole. Even further, make sure your future family is well taken care of. Then they could all thank you for what you did today.
Work harder and smarter. Save more and spend less. Start living healthily. Go fight for that special someone. Pursue your dreams. Educate yourself. Invest. Do whatever you need to do.
And. Stop. Making. Excuses.