Hives can be an indication of an auto-immune disorder, the problem is that they can also be indicative of many other conditions! My daughter developed horrible hives, like you, prior to her diagnosis. My husband and I would ice her down. For some reason, putting ice on the hives made them go away. They were so hot, that a cube would melt in about 15 seconds.
That would give her instant relief, but she also had to do the steroid packs as well as the benadryl injections.
I hope that you can start to feel better soon
Peace and Blessings
Look For The Good and Praise It!