Iodine & selenium are co-requisites, and one without the other are likely to cause thyroid problems.
After taking your 200mcg of selenium (L-selenomethionine preferred) with your supplements, then do the salt flush & pulse dosing in case of detox symptoms or if thyroid neck pain continues.
Some in my group have had to put a drop of Lugols into a bottle of water, then drink 1 ounce daily, and slowly titrate up from that dosage.
More here: http://tinyurl.com/iodine-references