Treatment For Painful Swollen Lymph Node On Neck

Hi, i am 20 year old, 52 kg wt. And 5"4' height. i have a lymph node swelling at the left of my neck which is slightly painfull and only occurs at the time of sleep. And i dont have any other problem. And have this swelling since 1 month i also had a treatment with a doctor but it wasnt effective as I still have the swelling...