Swollen lymph node

Hi, I am 16 years old and about 3 weeks ago i discovered a small lump on the back, lower right side of my head. It is painless and moves around and isnt too hard. After the first week, i went to see my normal physician who said it was a swollen lymph node, which seems to fit what ive found on the internet. He said it was very small, only about 2/3 a centimeter (personally i think its slightly larger but i suppose he knows better). He said it was probably caused by a small infection or virus that i might not have even noticed. It hasnt changed size for the 3 weeks, but it definitely hasnt gone away. Im concerned because of the fact that most sites say they should go away after 2 weeks or so, and also that it is painless. I have found things that say painless swollen lymph nodes could be a sign of some sort of cancer?? i know that 16 seems too young but i cant be sure. Im going to call the doctors, maybe see my physician, again in a few days but...anyways. i looked up the symptoms for non-hodgkins lymphoma and i dont have too many of the symptoms (and they all seem like they could be unrelated). I have the enlarged node on my head (which they say is uncommon). I dont have a fever. The only things that might point to it are my ear has been itching wierdly recently (again, could be unrelated) and in the mornings my stomach feels kinda full. Any help guys? Thanks in advance im just starting to worry about this!

[Dr Santos]

Hi,
How are you? In primary care settings, patients younger than 40 years of age  has a very small risk for malignancy, around 0.4 percent.  Localized lymphadenopathy may be observed for as long as 3 to 4 weeks. If there is no resolution after this time, further evaluation, including biopsy, may be done.  Try not to worry. Have your ears checked also by your ear doctor to rule out fungal infection as well. Take care and do keep us posted.