Have you read Dr. Brownstein's book: "Iodine: Why you need it, Why you can't live without it". He explains that when one is extremely toxic, the iodine transporters need extra help -- hence the co-factors. You should be salt loading every day to flush out bromide. The website Breast Cancer Choices has some really good iodine info on salt loading and detox symptoms (it is not a comprehensive list so you may experience symptoms that aren't there, however, if you come here and search or post your symptom, it is a safe bet that someone else has had the very same symptom. You should read everything on the iodine links and bookmark it.
Have you had a thyroid panel done that includes antibody tests for hashimoto's? I suspect that the reason that your goiter is getting bigger and not smaller is that you've got hashimotos. If that is the case, then you probably need thyroid meds (desiccated thyroid, NOT synthroid) in addition to selenium. Selenium should be added to your mix of supps. 50mcg at minimum in the form of selenomethionine. There has been some posting to this board regarding whether to add selenium if you have problems with mercury (amalgam fillings). We're still trying to figure that one out here on the board. But we DO know that mercury is toxic and will affect the thyroid adversely and if you have any amalgams, you should get them removed by a qualified dentist to reduce the possibility of being exposed to off gassing during the procedure.
Janie Bowthorp's website: Stop The Thyroid Madness is a highly recommended site for hypothyroidism. She has a link for recommended labwork and what the optimal values on the labs shold be. Please take the list of labs to your doctor to run. If you have to take the lab order to a lab for bloodwork, write somewhere on the lab the tests that you want run, in case the doctor doesn't request the right ones -- very common. Also be sure to read the section on THOSE DURN ADRENALS, folks with untreated or under treated hypothyroidism (that includes you) often find that they have weak adrenals that need to be supported and treated. The longer the hypothyroidism goes un or under treated, the weaker the adrenals become.
If it turns out that you do have hashimotos, then it might be a good idea to go gluten free. Many, many hasimotos folks find that they don't improve UNTIL they give up gluten. Stephanie Buist, a thyroidless cancer survivor, is an iodine advocate and patient of Dr. David Brownstein. She has stated on her iodine board that Dr. Brownstein suspects that her thyroid cancer developed from untreated hashimotos hypothyroidsm (her doctors KNEW about the nodules but did NOTHING other than WATCH her develop cancer). Her health did not really improve until she began taking the iodine cofactors and companion supplements, WITH the iodoral, doing extensive liver detoxing and going gluten free.