Ok, there is a bit to cover so I start with the basics.
The symptoms you mention is very hypo T, the thyroid tests are pretty much useless.
Taking your basal temp and observing other symptoms in the time to come will probably tell you a lot more than the tests ever did.
Are you taking the co-factors like selenium, magnesium,Vitamin B,C, real salt; as this will help both the palpitations and other detox reactions.
Since the palps comes a few minutes after taking iodine, my guess is that it trigger your hypo T condition.
the Iodine painting is great for joint pain, but dont do it to often as it will cause some skin irritation. Better to do it every other day, different spots etc.
An alternative is "magnesium oil" that can be rubbed as often as you like.
I would not stop taking Iodine at this point, rather adjust the dosage up, just dont take lightly on the companions.
Check our FAQ page, read old posts, the R`ed ones in particular, there is a treasure chest of info here.