Very late night and coffe???

Last night I had lots of coffe and stayed up till 4:30 watching movies and chilling out with friends. And two wierd things happened.

1. At about 4 we finished a movie and walked around the house, and I looked at a chair and there was someone sitting in it, I looked at my friend and told him, looked back and it was gone. Things like this kept happening for a while.
I was thinking maybe I was in a hypnogogic state from being tired but being just kept awake from coffee? And they were hypnogogic imagery?

2. I didn't expect to have a good dream recall when I woke up but I had the best most vivid longest dream recall I have had since I started my dream journal?

REM Rebound. Basically this just means that if you are prevented from getting enough REM sleep, are sleep deprived, or taking medications that suppress REM etc. then you will experience REM rebound, where the next time you do sleep, your REM periods are longer, more frequent, and more quickly entered. Which is why some people like to use sleep deprivation as a means to achieve a lucid dream. There's no doubt it is effective, but probably not worth purposefully sacrificing sleep over.

Hallucinations are common with any stimulant, especially when the effects of that stimulant are wearing off. Even more so when sleep deprived. Hypnagogic hallucinations are pretty specific to falling asleep/dreaming, and not used in such a broad manner as some people tend to think. You experience them when falling asleep. So unless you were nodding off when you saw these things, they were just regular old hallucinations. Or your friend has ghosts. :P

Nina, you pretty much said everything that I was going to say except one thing about hallucinating when you are sleep deprived. I am an HSC student in Australia i.e. chronically sleep deprived :p and I find that I often hallucinate at random times during the day, particularly when I have lost more sleep than usual. Anyway, I am not an experienced lucid dreamer and have not been able to induce lucid dreams but when I hallucinate I can control it in a similar way to lucid dreams. The only problem is stopping the hallucinations from dissolving. Say I am standing in a park. Out of the corner of my eye I see a puma. I look over and I, being a rational man, know that it is not really there but just a figment of my imagination. At this point I can make it move around or change form as I please BUT if I think about this too much, I reason that it can not rely be there and it vanishes :/ . Can anyone do this and does anyone have tips for stopping hallucinations from dematerialising?