I do suffer from cataplexy as well, yes.
I actually found out I had narcolepsy by doing a sleep lab for sleep-apnea as an adult. It kind of came as a shock since everyone else in my life thought I was just lazy as fuck. The ADHD diagnosis came years later.
I’m not an expert, but narcolepsy isn’t the only outcome for what you describe. It could also be hypersomnia, I think
I just scheduled an appointment with my GP and told him I needed a sleep lab. Insurance covered most of it, I think. I’m a little fuzzy on the details since it was a long time ago. If you’re in the US, you’ll likely want to make sure you get the details from your insurance company (assuming you have insurance; if not they can get pretty pricey). If you’re elsewhere, they’ll likely be free or cheap