hi sorry you have gone through this, its probably not due to the pcs this far out, have you started on any new meds or been doing to much take it easy , many years ago I had a similar thing it was due to lack of sleep, try to take a little time off and get your sleep patterns into sync, that worked for me it was a horrid experience, like my hart was pounding , some posters have had problems sleeping, lack of sleep causes chemical imbalance putting the wrong chemicals into our system a bit like trying to sleep when you are running well thats what it was like for me so I watch for the sign,s and always have meds on hand but go months and months whitout need of them its the opposite with me now though I am always sleepy

hope this helps

kind regards Vini