So you've been worried sick for months, maybe years, about some major problem. Only you know what. Eventually your nervous system can take no more and becomes highly sensitised. This only magnifies the problem to make it appear 10 times worse. The default outlook is always for the worst case scenario.
Often the problem is suddenly resolved. You weren't made redundant at 55 after all. In fact you're promoted and given a decent rise.
You'd expect such an outcome, the removal of the insoluble problem, would result in the dispersal of anxiety and all its distressing symptoms. But often, to our surprise and disappointment, it does not.
The nervous system isn't like a tap that turns on and off just like that. It continues to be over-sensitive until the fact that you're no longer flooding it with anxiety hormones allows it to gradually recover. No more panic attacks. No more phobia about leaving your home. No more health anxiety turning a sore throat into lymphoma.
But all that can take time. Be prepared to accept....and let time pass.
Sometimes when the 'big problem' yields we transfer our worries to the symptoms before they disperse. They take over the task of flooding our nerves with fear hormones and we enter a self-perpetuating cycle of symptoms causing anxiety causing more symptoms causing more anxiety ad nauseum.
These things are merely the shadow of the shadow: the transient after effects that are overcome by acceptance without fear based on understanding and reassurance and the willingness to Let time pass.