Mononucleosis...
So the 'worst' cold of my life that I have four weeks ago was probably Mono and the crap since then was DEFINITELY mono. Of course, now it's the fun of since I didn't know I had it for four weeks, possibly six weeks, did I give it to my baby and wife.
Thankfully now that they figured it out -- they are attacking the symptoms which is the only thing they can do with mono until it goes latent.
At least, I was only getting hit by one symptom at a time except for internally as the doctor says my liver numbers weren't optimal.
Well -- there's a reasonable answer that fits all the pieces even if it sucked the life out of me for a few weeks.