I ve been getting unexplained bruising hives for the past 3 years, the hives spread over my body and last around a week leaving a bruise. I ve had a punch biopsy but it came up clean. The hives appear on my thighs, arms, knees, palms of my hands and now soles of my feet. The hives are extremely painful, they swell. Then turn black 3 days after the hives leave. I get headaches, nausea, joint pain, and vertigo when I get these hives. Please help!