ckr1:
I would say don't worry about what other people think about your experience. You did have it and you do know it and that's all.
Some people have had what is called "lucid dreams" that might have led them to astral projection, and during the projection they reported to have seen these strange beings. You were probably in an Alpha state when this happened to you.
I had a very similar experience to that of yours about four years ago, but it happened in my bedroom as I was starting to have an out of body experience (OBE) previous to astral projection. I had voluntarily astral projected/travelled twice before this experience.
That sensation you described...not being able to move even if you wanted to, the sensation of being awake knowing that you were asleep, is the same thing one feels after being meditating for a few minutes and then falling asleep. When you want to astral project/travel, you start meditating, deeply breathing and quieting your mind (Alpha state) until you are deeply relaxed, so relaxed that your body feels asleep but your mind is awake). At this point is very easy to have this kind of experience.
I saw five of these short grey guys with big heads, big eyes, small noses and mouths (The type that is more commonly described by people who have had experiences with aliens). They were around my bed, looking at me. Then one of them put something in my nose (I couldn't see what but it felt like one of those plastic thin tubes they put you in hospitals during nasotracheal intubation) and I was so terrified that I thought my heart would just stop beating right then. My mind went blank after that (I guess I fell asleep) but let me tell you that when I woke up just a few minutes later, I could feel the sensation of having had something in my nose.
So, I can understand what you feel and what you say. I do believe in aliens. I have seen UFOs many times. People say that they don't believe in UFOs and/or Aliens because they haven't ever seen one. They need to "see" first in order to believe, but it's said that in order to "see" UFOs and Aliens you must believe first.
Maybe this is the reason for which those who don't believe have not seen them yet. They might not be prepared to have this kind of experience in this life, I guess.
Carole