The prolapse is minor - thanks for the advice -
You didn't say if any action/concern relative to the valve prolapse, is this condition under treatment? If the prolapse isn't severe, I believe it isn't considered a problem, and I read mitral valve prolapse occurs in about 10% of the population. I had a leaky mitral valve for years.
It is also clear we can aggravate health symptoms with our minds. Try to relax, breath deeply, focus thoughts and activities on things that you enjoy and then see how you feel. A visit with your doctor seems in order too.