As a lay-person reading comments such as these, one thing that puzzles me is I don't see thyroid issues mentioned. My limited understanding is whenever one has a illness thyroid hormones can be setback from it, to the point they are not even considered accurate or even tested in the aftermath of illness. COVID-19 is a major illness in some folks, so I would think they could throw thyroid levels off for a period. I myself have hypothyroidism & it is said thyroid hormones require optimal: vitamin B-12, vitamin D, folate & ferritin levels to function well (many other measures pushed online can make matters worse so please beware). Thyroid hormones can take a while to rebound, this is a slow process. You might consider checking your levels of B-12, D, folate & ferritin, & follow your physician's recommendations on optimizing levels. This measure has greatly helped me following illnesses, and I have had the lion's share of your symptoms.