What Causes Stiffness In The Neck And Swelling Above The Collar Bone?

My daughter is 7 years old. 20 days back she reported stiffness in neck.. We visited doctor as her neck on her right side above collarbone was swollen. We got X ray done which was okay. . Doctor recommended a Gel which we used 2 to 3 times a day on her neck.. We reviewed and got it checked again after few days as her lymph node above collarbone was swollen to approx 2 cm. It was neither too soft nor too hard to touch, but not so painful. Her blood test was okay as recommended to be tested by doctor. He also recommended milixim 100 with oflox 100 and ibugesic for 5 days.. which was recommended twice again for 5-5 days. There is slight improvement but not much.. my daughter is not complaining of any kind of pain in her neck and is behaving normal otherwise.. now Doctor is recommending FNAC test. PLEASE ADVISE.