Then you should read this article: Worry Isn’t Work – Dan Pallotta – Harvard Business Review. Key quote:
Worry isn’t work. Being stressed out isn’t work. Anxiety isn’t work. Entertaining a sense of impending doom isn’t work. Incessant internal verbal punishment isn’t work. Indulging the great unknown fear in your own mind isn’t work. Hating yourself isn’t work.
Work is the manifestation of value, and anyone who tells you that a person whose mind is 50% occupied with anxiety is more likely to manifest value is a person who isn’t manifesting much.
The part I highlighted is most important. Your goal at work should be creating value for your customers, your employer, and yourself. It’s the best way to maximize all three. If you are worrying all the time, you are never going to maximize them. You are never going to do the best job you could be doing.
Read the article. Think about what you are worrying over. Leverage the notion of achieving more value to help you reduce and eliminate the worry.