Hives

I'm 7 weeks pregnant and woke up with swollen, red, itcy hives. They started on my eyes, wrists, elbows and knees and since have spread EVERYWHERE and are much worse. My whole body is now covered in welts. My doctor said they could be caused by anything--and that pregnant bodies react more intensly to everything. Anyone have the same experience? What did your doc say? What should I do to make them go away? I've been taking benedryl and it isn't helping:(

Please help!! Thanks:)