Rub a kitten on your face. OH wait, you already tried that.
U said u didn't hav hardly any lotion on it cud be from the sun exposure while u were rafting try sum aloe vera gel. If that doesn't work I t may be a reaction n u cud take sum benedryl and put cortizone on affected area hope this helps good luck
A Dermatologist can actually see and tell you what has caused it.
Sounds like an allergic reaction or hives... Get to a genuine dermatologist if it continues and you're worried about it.