CataChris - I can relate with you, to a large extent, I think.
Very much, at first upon discovery/realization (when 28-30) of having the disease, I did not think there was much or really any possibilty of what I had, being Narcolepsy with Cataplexy.
I'd been collapsing for over 8 years, as a kid I couldn't lift my arms while being tickled, because they were limp and muscle-less.
I had 5 sleep studies before an MSLT (which are really not a good, no where near 100% accuracty, test -according to David B. Rye, MD, PhD of Emory edu-) because a unusual 'sleep apnea' was discovered.
'Idiopathic Central Sleep Apnea' is a rare form of sleep apnea were the brain and respiratory muscles communication is messy. Mine thankfully, is only minimal-moderate, but I had many months of real troubles/ordeals and intense (500%+) escalation of the severe (collapsing) Cataplexy.
Prior to discovering the word 'Cataplexy' after doing a search of "laughter AND paralysis" on the internet, after collapsing with a friend who'd had a potty accident while crossing a street in Mexico (we were attending a other friends wedding, and he'd had the Poo's for a couple days), it was funny but collapsing on the corner was not...
Anyways, I'd never considered myself to be tired, yet it had disguised itself to me that is, all my friends seemed to already know or note that I was often ('normally' -I hate the word 'normal'-) tired.
I did get the dx of 'Probable N w/ C' after an MSLT was done at Mayo Clinic, the 'probable' was due to my 'mean sleep latency' being 9.5 minutes which is above the 8 minute rule of diagnosing N; and Mayo is thorough.
Also, they offered me a spinal tap to check my Hypocretin level/s, to give me a more definitive dx; but since I'd been there 3 weeks already, had a long bus ride coming up to return home, wasn't expecting any treatment or anything positive to come from having it done, I passed it up. I'd not complained one bit about tiredness, only about Cataplexy; they thought it was unusual.
As time has gone on, the more I read of other experiences as well as the more that I learn about the disease (including what seems to be more and more research being done, new discoveries like the 'excess antihistamines' for example), and the more I reflect upon my past; it becomes very clear and obvious that this is the disease that I have.
Today, I know I'm often tired, as I've managed to through 'lifestyle adjustments' come a long long way from where I was. I was very fatigued prior, I disovered many allergies and I worked on minimizing them. One major thing I did was changed my diet, eliminating Gluten and Dairy has been Hugely Beneficial. Now, I'm not fatigued or with Migraines and headaches, like prior; yet I have sleep attacks more distinctly now...
You'll learn a lot as you read through research and others experiences. Reflecting is a good thing to do, too. You gotta keep your head up and do your own research as unfortunately, not all doctors know enough or accurately.