Lymph node in neck

I asked a question earlier, but it got off track a little. I found a small pea-size lump on the right side of my neck, about three fingers in distance (using index-middle-ring) up from my collarbone. I showed it to my surgeon (am 1 yr. out of treatment) and he made light of it and said that it was a lymph node, but very small, and that the cancer wouldn't move in that direction. Now two months later, it hasn't changed in size, but it's still there and causing me sleepless nights (when you've had cancer, you see these things much differently). I went online and read in the doctorsloung.net that a "next step" would be a CT scan of the head and neck and that "a biopsy of the node is only done as a very last resort as it has serious drawbacks on therapy if it does turn out to be cancer." Any experiences, comments, etc.? I really, REALLY appreciate your words of advice. Thanks, Jojo, for speaking on it earlier.