I think it's highly unlikely that these are bromine detox symptoms. I'm glad there are a few things you're taking that seem to help. Be sure that one thing you take is 200 mcg selenomethionine. Is there anything you do on that 3-day cycle, such as a day on which you exercise, or something you eat that you don't eat every day? Along with antibodies, there is other thyroid testing that would be useful. If you do have Hashi's, you may have food triggers that set up your immune system to react, attacking not only your gut but also your thyroid. One of the most common is wheat protein.