Like others, I've had dreams where I couldn't move, or was in danger and couldn't escape, (something was falling and I couldn't get out of the way or I was being crushed and couldn't get out of the situation).
In my dreams, (or nightmares) there are no "dark creatures."
Usually it's a thing or an object that is threatening me, (a wall is falling and I can't get out of the way).
In the dream it's scary, but as soon as I wake up I'm fine because I know it was a dream.
But I do believe dreams are messages or indicators of things going on in my life. I try to connect the dream to something that is happening. Am I under a lot of stress? Is something going on that is "pressuring" me? Am I "conflicted" about something?
When I take the time to examine the dream and make the connection and figure it out, the dreams go away.
Another classic was when I was in college. Around finals time, I would ALWAYS dream that I had signed up for a class and then forgot to attend until finals week. The dream was always the same, me running across campus, down the hallway of one of the buildings, arriving just in time to meet the professor leaving after the final exam was finished and telling me I was going to get a big, fat "F" for not attending or doing the work.
I hated that dream.