That feeling you have as you fall asleep is when you're in an alpha state. Alpha dreams begin to come. These are not exactly real dreams, they are precursors; your mind just having a bit of fantasy. You are not paralyzed yet, as you are when you are sleeping, and so sometimes you trip or fall and jerk awake. It's also a sign that you are remaining conscious until the moment you fall asleep.
Erin Pavlina, Intuitive Counselor
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