I'll bet it is an eye twitch caused by lack of magnesium. When I took high dose iodine, I had more twitching, Iodine seems to increase the use of magnesium by the body.
Get magnesium glycinate,chloride, taurate or the citrate (natural calm). You don't want aspartate as that can be neurotoxic. Most of the other forms are not well absorbed. It can take months to build up your mag levels. Epsom Salt (mag sulfate) baths help too, but I think you still need a good oral form.