I have trouble discerning dreams from reality when I'm sleep deprived (like haven't slept for 4 days and finally get a night with some sleep). I also have like, dream delusions when I first wake up if that makes sense. Like the physics and various rules that applied in my dream still apply to me when I wake up even though that doesn't make any sense. Like one time I woke up beleiving that people had dragster horses instead of cars.