What Causes Itchy Bumps On Arms And Legs After Drawing Blood?

I had blood drawn last Friday (I got sick from my boyfriend maybe two weeks ago? and my tonsils still refuse to stop being swollen, though I m fine otherwise.) but now on my right arm (where my blood was drawn) I have itchy bumps. The bumps are only on my one arm, but a few days ago my legs were itchy and so was the small of my back. I assumed they were flea bites since my dogs have been sleeping in my room, but they d be on my other arm as well, wouldn t they? They aren t very big and they don t puss up, but it s bothersome.