If you are using a brew bag; check it. You may have burned the bottom or left a plastic stir spoon in the pot. I have burnwd my brew bag and essentially the melted (burned) polyester fumes come up through the wort and burn yiur eyes and nose. It is why it is a good idea to donthis in a well...
Having same burning eye problem heating wort using an electric burner.... 37 other boils had no problem. This one is a copy of the fist one I ever tried and wow is it burning my eyes. Thinking maybe a microbiological contamination that had a bad byproduct that off gasses something acidic.