I’m absolutely not telling you this is what’s wrong with you. I’m just sharing that I have kind of similar issues going on. I’ve had low energy and been needing extra long naps for a few months, it may have started before but I had covid in April but it was not particularly severe. I haven’t noticed my temperature being elevated but I’ve definitely had bouts of high heart rate for a given power, muscle soreness and a lot of apathy. I had blood work done and came back with vitamin B12 and and almost zero! So my doc put me on over the counter supplements. But now we have to figure out what’s causing that condition because I have a pretty good diet and I spent a lot of time outside so vitamin d and b should be much better. Other than that, keep after it my friend! You’re the best advocate for yourself!
@rrutis Thank you for the input! Definitely something to keep an eye on. And there are probably some hormones and vitamins I could be tested for that I haven’t looked at. I’m suffering from investigative medicine fatigue, so I’ve somewhat resigned myself to the current state, at least for the time being.
That being said, I got the latest covid booster today. I’ve seen some potential studies or analysis that seems to showi that getting a vaccine booster has helped improve symptoms in some long covid sufferers. So, fingers crossed for that. 
Sept 1 (a week and a half ago) was a full year since I contracted Covid back in 2024. A year ago today I was in quarantine in my backyard.
While recovering I barely even rode or exercised until January. I wasn’t able to even attempt Half Monty until May. I had been riding with a manual FTP of 185w, but rarely rode my bike except for easy recovery efforts until April when I did my month of SUF shenanigans. That HM in May put me at 215w.
I am now three weeks (including a restart) into my first training plan in over a year. My Zone 2 power HR has been low which has been a great sign. And also meant I needed a retest. So I did my first healthy Half Monty this morning. And I am excited to say my 4DP numbers are finally above what I consider my baseline, and back to being close to what they had been before I got sick over a year ago. My FTP after today’s HM was calculated at 238w, up 23w from May. By comparison, my HM FTP in Nov 2023 was 252w, and best ever in Dec 2022 was 276w.
I still don’t feel 100%. Still don’t have any answers. Still have some extra lingering fatigue and elevated body temps, but I am the closest to normal as I have been in over a year. And for that I am thankful. 
Aside from still having no answers, some lingering fatigue and elevated body temps, this is excellent news @emacdoug !