What Causes Frequent Night Sweats And Swollen Lymph Nodes Behind Ear?

Hi,My name is jake i been geting night sweat pritty bad almost everyday for past year or two and sometimes i wouldnt get em i have a swollen lymph gland behind my right ear and i got blood work done abought 1month ago plz help me this sucks btw the lymph node behind rite ear is abought size of a nickle and has no pain