Sleep!!
That's a topic of "sore" discussion in my household. My husband is bothered by the fact that I can't seem to sleep at the "Right" times!
My sleep-pattern sounds very much like yours. There are times I get so tired so fast, that I just crawl on the floor and sleep where ever I happen to be (for about 30-45 min). Years ago when I was still working, I would sleep (head just fall over) as soon as I sat down on the couch at home. It didn't matter if someone was talking to me or if I was eating, I would just fall asleep! One day my dh said, "You act like you're on drugs," at which point, I looked at him sweetly and said, "Why dear. I AM on drugs, and lots of them, too!" That can contribute to the problem, but fatigue and insomnia has been with me for about as long as I can remember. I think I must have used UP my supply of dopamine, because for years I could get by on 2-4 hrs. of sleep and be so perky the next day and not nap (pre- PD dx). My teacher friends would get so irritated at that one
"quality" I seemed to possess. Even though my DR shakes his head and doubts it, I've always wondered if my burning the candle at both ends for so long (no sleep) was some sort of pre-curser to my PD or if it led to the PD. Since we don't really know the cause of PD and it manifests itself so differently in people, we can just add that to the list of "I wonders?"
Both of my children are also night owls. I am very fortunate that Ambien works for me, no bad side-effects, around 1:30 or so, and keeps me asleep for more hours in a row than I could ever accomplish on my own. I think I have read every sleep-book, or listened to white noise or ocean waves to sleep; I feel like I have tried everything (even writing lists of the day's troubles and throwing them away, to empty your mind, to earplugs to drown out my dh's snores, to special pillows, etc. etc). I don't always get the sudden drowsiness now that I can stay asleep, but it's the getting to that stage I still struggle with. It's no wonder that the older I get, the worse the bags under my eyes look!!
CC