The worry and the fear that you feel right now is in the future. There is nothing to fear right now, if there were, you would not have time to feel “worry”. To worry takes time.
Ultimately, the answer is to accept the feelings you feel, because it is the “resistance” of them that is causing the mental ,and sometimes physical pain, that you are feeling. The thing that you are resisting, is the reality of the way things are right now.
But, we want this “pain of worry” to go away. However, first, for a moment, accept the worry, accept the pain. This is what you are feeling right now, this is reality, recognize it, and accept that it is happening right now.
Now it is less, the thought are still there, how do we prevent the thoughts from turning into full blown worry again? It is impossible to stop thinking. The human mind cannot be turned off.
The “worry” is in the future. We are not God, so we do not absolutely know what will happen in the future or how we feel when the future arrives. Can we accept that?
What else are we “resisting” - that we can stop resisting?
This fact may help, “This will pass”. Nothing lasts, everything is “impermanent”.
You will laugh and be happy in a future date.
And yes, one day you will worry again.
(With thanks to Buddhism for Beginners)