For your differential diagnosis, please consider the possibility that the Iodoral may be causing a higher level of antimicrobial die-off, releasing dead bacteria, viruses, fungi, etc., into the bloodstream.
For some reason, THIS one area of your body (damaged lymph?) cannot digest the corpses of the dead microbes and your body is attacking the undigested debris.
My first level of experimentation would be to take digestive enzymes to digest the dead "cooties." Then let the white blood cells scavenge the rest.