Hi. I had unprotected sex before 40 days. I have mild middle back itching for past 35 days. I go to gym and sweat a lot. I had eye itching and less pain for the past 3 weeks. I have right shoulder pain and neck pain from yesterday. I went to std clinic. Blood and urine test taken and it was negative. Now from yesterday I have headache. I read about swollen lymph nodes and started to check for it by strrongly pressing it on my right side of neck for the past 15 days. It caused pain on why neck. Due to this on my right I see a small not moving nerve or node? I don't know whether it is a node or nerve? I went to a gp and he said it is an allergy? When to fear about lymph nodes and at what size? I am concerned about hiv. Does this an hiv? Does pressing nerves on neck and collar bone cause feeling lymph nodes and mild headache?