Wow, that's crazy! Thank you for the heads up. I hope your skin will heal soon.
if anyone wants to research it further, if you type in to google "photodermatitis lime" you get the best results and pictures too. not too much info on how to take care of it except for moisturizer and hydracortizone.
i just wanted this here incase it happens to anyone else so they have the info, because typing in 'brown spots on hands' only brings up age spots and liver spots.
A friend of mine had it happen about 15-20 years ago. She was squeezing limes for Margaritas while camping. It happened on her palms but it was red, itchy, like contact dermatitis. It only happens with Mexican limes. My understanding is that it is a variety that is particular to Mexico.