As Citingsources says...your thyroid is probably toxic with bromide and you have a lot of detoxing to do. When the symptoms become too bad, stop and let the salt pushes move out the bromide. Liver supporting herbs and supplements like n-acetyl-cysteine will help a lot since the liver can get congested when the bromide starts releasing.
Keep taking the Iodine and work your way up to 50-100mg. The fact that your thyroid has nodules means you are very deficient.
The bromide detox symptoms can get pretty uncomfortable, but keep at it and follow the protocol on the link I posted earlier.