You may need to do some organizing, goal setting, or writing. Or maybe all of these. If you're worried about how you might have screwed up the past, you might want to write (or type, whatever) to organize your thoughts. If you're a more verbal person, maybe talk about these things with someone. If you get things out of your head and into words, it can help you organize your brain so that instead of foggy, murky chaos, you can start to come up with a plan of action for dealing with the things that you believe are bringing anxiety. Make some (reasonable) goals, with deadlines, and try to meet them. You may need to adjust them as you go, or you may do them terribly at first. This is fine. Just keep going.