Clinically Isolated Syndrome is not new...it really is a description of what you had early on -- an isolated attack of something that SEEMED to go away, and didn't appear to have damaged your nervous system (didn't show up in the LP).
If I were you, I'd go back to your pcp, remind him of the earlier attack, and ask again about a referral to a neuro. If he still refuses, then change physicians until you find one willing to make that referral. Clearly there is something more going on, that just didn't show up in those early years.
You might also check the web to learn about fibromyalgia, to see if any of your current symptoms are similar. I do know that there are many symptoms that are alike between MS and fibro, and it COULD just be that your current flare is a flare of fibro..but you might want to research that a bit, and see.
...I am not a doctor, nor health professional, and don't pretend to be one, here.....