If you started Iodine within several months and found yourself having gained weight, then you probably needed to do so. Your body will go through a lot of changes in which most are inexplicable. If you have no other overt symptoms, then I'd keep going. Give it a year and see how things go.
If you have Amalgams still, then you needed to take them out preferably before you started iodine. If you're interested in chelation, reading the Amalgam Illness book is a great way to start learning about it.