Is worrying useful, if it is when should you start to worry?

You are worried about the results of your test/ interview/ about whether your publisher is going to accept and publish your manuscript etc. and whatever you can relate to.
So how long before should you start worrying?
This is may seem controversial,
The answer is, “you should never start worrying”, it’s bad advice to worry about something.
Worrying doesn’t change output or present process. Also, it ruins what useful things you may be doing that day, it’ll distract you. And every time you’ve fooled and tricked your own self by putting yourself into thinking that it is useful or it cannot be avoided or it can be used as a fuel, but it is not. Believe it or not, accepting this fact is easy, but executing this is even harder. Even though I am writing this, I know at least that I too worry and it is of no use, but understanding it deeply requires consistent acknowledgment to yourself about what you are doing worrying comes into the picture.
Because if you’ve started worrying,
Now you’ve one more thing to worry about.