I've been covid negative for a month. I was on a 7-day bike tour and got glutened (celiac disease) at the same time a fellow cyclist infected us with covid. It was a cytokine perfect storm. Three weeks after testing negative I went on a 12 mile easy bike ride (still fatigued), with subsequent heart-trying-to-beat-its-way out of my chest and pain. Doctor thinks I have myocarditis, so I manage exercise by taking a lot of rest breaks, until the day the inflamation is gone. I have noticed that the pain and blood pressure is worsened by anxiety (including bad dreams), poor sleep, and too much exercise. I try to escape in hobbies and upbeat books/movies. It is tough finding friends/doctors to talk to, so support groups are important. If you can read peer-reviewed medical papers, another source is ResearchGate, which is mostly scientists uploading our published papers. It wasn't many years ago that doctors thought celiac hit one in 5000 people, instead it is about 1% of the population. It is likely that "rare" myocardia and other covid symptoms will follow the same track as more is learned.