Concerning tincture of iodine: please help. I don't know what I've done.

I was stressed insofar as forgetting how to properly take my meds, and so I applied a half a dropper of a tincture of iodine on the underside of my tongue. Immediately upon contact, I spit it out and proceeded to rinse my mouth. However, about an hour later, the affected area still has a slight burn and feels dry. Furthermore, that metallic taste still remains. Should I be worried, and are there any oral remedies for this?