i am breaking out with hives all over my body. i havent done anything differently lately to cause an allergic reaction, and i am not allergic to anything as far as i know. they seem to be coming and going, not really focusing on any particular spot. ill get an itch, ill scratch it lightly, then it starts to itch more and more, little red bumbs and raised skin start to appear. after a while, if i can keep myself from scratching, it goes away. it just keeps happenning all over my body. what is this rash?