My first thought was that you had triggered an adrenal problem. The thyroids & adrenals have a symbiotic relationship. I had abnormal stress responses when I first started taking thyroid meds & had to stop taking thyroid meds til I resolved my adrenal problems BUT I was reading Dr.Mark Starr's book who said he used to do this also while treating patients BEFORE he added Iodine to the protocol.
I would suggest doing the barnes basal temperature test at home. Do it at 5a.m. is when temperature is at it's very lowest for 10 days. (make sure you've been asleep at least 4 hours prior to testing)
"barnes basal temperature test" -
Dr. Barnes recommended that you measure your left underarm temperature for ten days in a row first thing in the morning before doing anything else at all (going to the toilet etc). Movement and activity of any kind raises body temperature and invalidates the results. The thermometer should be shaken down at night before going to sleep to avoid having to do so in the morning (unless of course it is a digital thermometer). Menstruating women should start this ten-day period on the third day of their cycle. Many health care practioners who recommend the test now suggest a longer time period but Dr. Barnes felt 10 days was enough for an accurate assessment of thyroid function.
The underarm temperature is actually lower than that measured under the tongue so 36.6-36.8C is considered normal in the BBTT. Anything below 36.6C (97.88F) is considered an indicator of possible underactive thyroid function while anything above 36.8C (98.24F)could indicate an overactive thyroid (although of course it may be a sign of infection and fever or other problems).