pinky, the things that stand out, to me anyway, are how the first was there for years, and how the number has increased.
This could be lipoma or sebaceous cysts. If you are rubbing the area a lot, that might result in inflammation. But looking at the least favorable thing, that'd be Hodgkin's Disease - because of your age and the location of the nodes. Most people with bumps don't have lymphoma, but as we know, ultimately some people do. My father had a bump on his neck that he was obsessed with, that his doctor dismissed (according to the odds) as harmless... and it did turn out to be lymphoma.
So are you saying that even without other symptoms for years now, that this could be lymphoma??????
the odds are that it is not, but yes that's how it typically goes.