re: I faint when I laugh too hard

Oddly enough, narcoleptics sometimes struggle with falling asleep at night or catch a second wind when it’s time to be going to bed. If you’ve seen a cardiologist and it’s not vascular then I suggest seeing a sleep specialist and having a sleep study done if they recommend it.

ETA: cataplexy is a symptom of narcolepsy. It’s the loss of muscle control caused by a strong emotion (laughter is the most common).