Has anyone had a rash that just wouldn't go away?

So I have had a rash that appears in welts all over my body for the past almost three months. It welts up and itches like CRAZY and than will be gone 10 min later only to reappear somewhere else. Well this went on for almost three months and than about 2 weeks ago I started getting red spots that were about the size of a quarter some of them in clusters all over my leggs, hips and stomach. On top of that all I have been so tired! I have no energy...last night I slept for 13 hours and was still tired. And than this last week I have been having dizzy spells where the room would just start spinning. Has anyone had ANYTHING similar to this...I am stumped!