Iodine and hear palls thyroid meds

I was taking Nautre throid (4 grains) a few weeks ago and upped my Iodine to 5mg from 2.5. Within a day heart palls, inner shakiness like anxiety of the body, HIGH temps (waking temps went from 97.9 to 99.9) and things didn't settle down until I dropped the nature throid to split doing 1/2 grain three times a day...for one day I felt better and then same thing started. I went to doc (she wanted an EKG and it came back irregular but I DO have mitral valve prolapse so that could be the reason and the nature throid seemed to make it worse). Is it possible to have low Free t3 (2.5 range 2.0-4.5), low Free T4 and that the Iodine thyroid med combo be pushing my adrenals into overdrive causing this stuff? I am OFF the thyroid meds (my doc was nervous and I have a cardiologist appt next tuesday) so wanted me off everything. I have hashimotos and I am not afraid of iodine..I am more convinced it helped cause my hashimotos and want to continue on the protocol (especially with high bromide (rash and all). my TPO antibodies have been steadily dropping with iodine, LDN and a CLEAN as hell diet.
Thank you for insight on this. the high temps and heart stuff is thrown me off.