I have this... quirk. More than once I've sprung from bed in the middle of the night, flung my bedroom door open, and raced to grab the fire extinguisher... only to realize I'm not in the midst of a goddamn blazing inferno. It's happened two or three times now and it's pissing me off.
It's really upsetting because I go from deep, dead-to-the-world sleep, to wide-awake adrenaline surging mania. When it happens there's no going back to sleep. It really sucks because I have a huge exam tomorrow that I'll need to study for until the wee hours of the morning, but I only got about three hours sleep last night. Errgh.