Are you drinking enough water (and consuming at least a quarter tsp of GOOD salt (like this one) for every quart of water needed?
(The suggested amount of water consumption is half your weight in ounces of water daily.
Kidneys need salt to squeeze out the toxins that are collected there. You need to be drinking plenty of water.
You need to be eliminating well so that the toxins (released from the iodine) don't back up on you and cause you problems.
Last but not least I will tell you what happened to me. I kept going backwards, too. I needed to face the music that I simply HAVE to cut back on food consumption. Could this be a problem with you, too?