Well, Jaq, the worst I'd had was being in bed for two days straight. I'd sit my way down the stairs once or twice per day. That would be followed by days on the couch. Then I'd be okay enough to get to the supermarket to not starve

That repeated for a few weeks.
When I was mobile, I'd exercise at home with the weights for a minute or so. Then I'd
pay the price for a day or two; then when I knew that I was ready I'd start the cycle again. A fixed schedule would have been very wrong. I was doing the exercise because after each cycle I was a little better, more capable. Plus, I really love it - life was boring without it. Gradually, things got better. Taking magnesium was probably the only supplement that I was adding regularly - though I'd always been health conscious previously.
There was a bout of possible viral myocarditis, but I won't go into that.
Things went up and down, but always the trend was up. I've been exercising almost like normal for a year and a half at least. And oh yeah, I haven't had much fatigue or brain fog or whey allergy anymore since taking the (sulfur containing) MSM. I've still got temp and BP dysregulation, swollen nodes still, sometimes mild headaches and
always that feeling of something wrong in my head - plus the histamine effects. Never pain.
Are you still zooming along today?