WZ,
I think I answered one other time but I had the same type of neck dissection as you; however, no RAD. It has been almost 2 1/2 years and my neck and tongue still are tight. I have come to believe, that it will always be this way. It really doesn't bother me much anymore. I do however, every once in a while, get some sharp pains or just a continual dull light throbing. Normally, it is when the weather is about to change or it is very damp and cold.
I would however, call the doctor and have everything checked out. Hope this helps some what.
Take care.
Anne.