Newb Question

I feel kind of bad posting here but here goes. My symptoms compared to "real" long Covid are minor but they are still impacting my life significantly.

I have been dealing with a very puzzling set of symptoms that I feel can be traced to a case of Covid about two years ago. It wasn't particularly bad as covid can go but after the illness I have not been able to exercise as much as I used to. About a year after that I got what I call an Atomic level cold (not covid, I tested) and my ability to exercise went down again.

The most striking example of this is two trips I made to the High Sierras. One, before covid, went fine, I hiked with the energy I am used to. A year later, and six months after covid I did the same trip and the same hikes and was out of breath, resting every 100 yards and had this weird tingling in my arms and legs.

I have self diagnosed myself with possible post viral syndrome. But I don't know. Two doctors have done blood tests looking for immune system issues or Epstein-Barr. All the tests come back negative. I am not very happy with either doctor, they are doing the minimum effort and are mostly interested in getting to the next patient.

My question is what kind of doctor might be able to either confirm or rule out a viral cause. I live in Ventura County, Southern California and it would be nice to find a doctor in the area that has experience with covid/viral issues.

Cheers.