Hello: I have been a sufferer of OCD for many years, and for the past three, I have been particularly worried about HIV. I have had several tests and they have always come back negative. Last week, I went for another test, and now I have anxiety over having been infected while having my blood taken at the lab. The nurse did not wear any gloves, and after she cleaned my arm with alcohol, she started tapping my arm to find the vein. I think that the entire practice of having cleaned the area was a waste of time, since she touched it afterward without a gloved finger, and then inserted the needle. I am now worried that her hands might have been contaminated, perhaps from the person whom she took blood from before me. What are the chances of being infected in this way? I also noticed that the nurse took the cotton ball from me afterward which had a bit of my blood on it, and obviously was not too worried about coming into contact with someone else's blood. Am I overly concerned?

The nurse should have worn gloves, but you cannot get HIV infection from the process you described. It requires a large dose of virus (a significant amount of contaminated fresh blood) and a deep exposure (blood injected or in contact with a deep cut or wound).