Detox was initially quite difficult and unpleasant also, and I felt quite sick and developed Iodine mumps (enlarged glands in the neck) but 12 months later my remaining thyroid tissue has shrunk nicely back into my neck and I look normal again. You can now see the hollow of my neck which was not visible before for many years.
It takes alot of poison and deficiency to get a large goitre and it will take some time in detox to get it to shrink; so it will be a journey, and healing will not happen overnight.
Excesses of fluoride and mercury in combination with an Iodine deficiency were factors responsible in me growing mine.
If you have mercury in your teeth you should consider getting it removed by a biological dentist, and also getting a water filter that will take care of removing fluroide from your water supply.