I did actually have a lifting of what I call brain fog. Iodine must have something to do with the brain. It could be chelation of metals helping your diminished depression. It could also be Iodine finally attacking parasites. This is all difficult to tell.
I have consumed that much on a daily basis without indigestion. One thing you could try, is to take 1/4 teaspoon of baking soda (bicarbonate of soda) in a glass of water; just to see if the indigestion is related to acid. Once, I did have some acid related problem with my kidneys that went away with this trick.