Procrastination does not at all characterize your attitude to work or competence, it's just a model of behavior that helps to cope with stress.
How it works
Imagine that you were sitting on the beach and noticed that a child was dying near you. Hardly you will begin to think about what to do, you will immediately rush to the rescue.
1. Recognize that you are experiencing stress
Do not analyze and do not think. Just accept that your condition is not some kind of mistake or defect, but a natural reaction of the body to stress. And this stress affects how you make decisions. So you will remove some of the tension and "unlock" the prefrontal cortex, which turns off during stress.
2. Give yourself five seconds to make a decision
Do not focus on how to cope with stress. Quickly make the decision to do the exact opposite - spend the next five minutes to work on what scares you. If you put off the phone call, pick up the phone and call. If they could not begin to write, in five minutes, write everything that comes to mind. Perhaps you will get nonsense, but you will overcome procrastination.