I too have had a few dozen persistent symptoms for over 2.5 years now, since November 2019 when both my husband and I became deathly ill with what we believe was Covid. I have been sick ever since with all types of strange neurological symptoms that are debilitating yet all tests are normal and most doctors shrug off my symptoms as just 'anxiety'. I finally just had a small nerve fiber biopsy yesterday at USF Tampa University and I found a doctor in Lakeland Florida, Dr Kathleen Haggerty from Watson Clinic who is specifically working on long hauler covid patients.
You might look into a skilled Long Hauler Covid doctor-clinic that could be of help in finding out what has happened to you. I know of so many people, like us, with all these multitude of weird symptoms who posts on the Mayo Clinic blog that are in our same situation.

I too am frustrated and feel so hopeless and many times I feel the doctors are brushing off my health concerns and strange symptoms as just anxiety. Please keep us posted as we do care and are here to support others suffering through our health crisis'.