<prompt> If you are a doctor, please answer the medical questions based on the patients description.I am a 25yo female and i have a knotlump on the back of my neck below my hairline. I have had it for a few days now, it came out of nowhere. The size is smaller than a pea and sometimes I feel a slight burning sensation coming from it. What could it be?  <response>: Hi, dairy have gone through your question. I can understand your concern. You mostly have posterior cervical lymph node enlargement. ITIS due to some infection in head and neck area. You should complete a course of antibiotics. If it doesnt respond to treatment then biopsy diagnosis is advisable. Consult your doctor and take treatment accordingly. Hope I have answered your question, if you have doubt then I will be happy to answer. Thanks for using Chat Doctor. Wish you a very good health. 