Signs your brain is about to turn that pleasant dream into a full-fledged nightmare:
1. Light switches no longer turn on lights. Remaining lights turn off.
2. Running from danger but legs turn into molasses.
3. Back in school in a class you forgot about all semester on exam day.
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4. Aliens.
5. You wake up but you're still dreaming but think you're really awake.
6. That nagging feeling something is following you and you turn around and only hear something following you because the lights don't work.
7. Impending sense of doom overshadows everything.