Hi, you're not being paranoid. I'd want one of the nodes sonogrammed, probably the largest one.
What you have is probably some strange inflammatory process, because cancer wouldn't spread from Virchow's node (left collarbone) to the neck like that. A sonogram can give very strong indication that a node is benign (like having a 'fatty hilum'). So the scan can set your mind at ease - but then you'll still very much want to find out what is going wrong anyway. I wouldn't just ignore those symptoms, of course.
How large is the largest node?
Try this thread:
http://www.medhelp.org/posts/Leukemia--Lymphoma-/Swollen-Lymph-Nodes-after-alcohol-consumption/show/385680
It's not always caused by cancer, as you'll see.