We have said it here before, that published studies show that almost 30% of stage one and two patients who show clear nodes on scans at the time of surgery, actually have occult micro mets to the nodes, which do not manifest themselves into something scanable, or palpable for as long as a year to 18 months after treatment. Having said that, the fact that it is painful is likely a good sign as positive nodes are not usually painful. This is not an absolute, just a general clinical impression. Infections in the ear, tooth abcesses, etc. all. can drain into the cervical nodes causing them to become inflamed, enlarged and painful. But you are doing the right thing...get it check by someone in the know.