We regret so much about what happened in the past, and we worry a lot about what may happen in the future. Here is a basic fact: you no control over what happened in the past. It brought you where you are now. There is only one thing you can do about it. Learn about it. You waste a lot of energy when you keep on looking into the past with regret. All you have to do is to wake up and life the moment you have with purpose.
Worry is almost always associated with the future. You worry that you may not get the results you expect. You worry about your visit to the doctor. When you worry, you strangle hope and stop your system from getting the energy and the momentum it requires.
Do not worry. Worry is useless. Stop regretting about the things you have done in the past that may hurt your future. You have the time now to get them right. So, instead of worrying about those things, just move ahead and do what is right.