CALLING ALL EXPERTS-Pepe, Hopinso, Zoebess, or anybody else with insight

I am an experienced MCer, with some very new symptoms. I posted yesterday about heartburn...this has passed (though it did last 10 FULL hours). I also mentioned some itching. Well, the itching has turned into full on HIVES (head, neck, ears, eyes, chin, palms, knuckles, elbows, ribcage, hips, and foot). I've never had hives before, nor have I ever had ANY problem with the MC. Can somebody PLEASE shine a little light on what is going on. This is only my third day. And also, some home remedies for dealing with these things would be MUCH appreciated. The more I scratch, the bigger they get!