TGF,
I completely agree with Mark and Brian. If you your symptoms haven't disappeared, have it checked out right away with a biopsy, either by an ENT or oral surgeon!
Like you I had an asymptomatic lump on my palate that actually became smaller between the time my dentist noticed it and the biopsy. To everyone's surprise it turned out to be malignant, but since it was found at an early stage, I got away with surgery only. I am not suggesting that whatever is going on in your mouth/ neck is cancer, but at least get peace of mind by having it checked out with a biopsy. Hope everything will turn out well, and you won't become a member of this club.
Good luck!