I’ve been on top of epicenters of small quakes twice. The first one I was awake for, and it was just one big jolt. I honestly thought a car hit our building (one of those 60's buildings supported by skinny posts with the tuck-under parking) and I went outside to check before realizing it was a quake. The second one woke me up at 5am and it scared the living crap out of me, that was the most frightened I think I’ve ever been.