This has happened two times:
I crawl into bed and start falling asleep. While I'm falling asleep, I listen very carefully to what is going on around me because sometimes I'm afraid (when I'm alone in the house) that somebody will break in through the door.
All of a sudden a rushing sound/feeling slowly overcomes my entire head and I am unable to open my eyes, move my arms or legs, or speak. I am terrified because all I can hear is this immense rushing/ringing sound and I am unable to hear if anybody is entering the house or see if anybody is in the room with me. During this time I am trying my hardest to move my arms or open my eyes but nothing works. I don't remember what happens after that, I just assume I fall asleep.
It's one of the most terrifying things I've ever experienced! What causes this? Is it just a nightmare? It feels like I'm awake during this..