No shaking or hum in an indeterminate city in the southern half of the U.S. where I am now. Where are you, 184454?

Sabrina, I know you probably already thought of this, but the best idea I have for the noise is the jets you keep seeing. If the lights were turned off and somebody was holding, say, a high-altitude mock dogfight somewhere above your home as military training, you might get that sort of sound. If it is a training exercise, one would expect that the hum varied in intensity over time as the center of the activity drifts towards and away from you.

Crap, they could be playing with an electrostatic hovercraft or a UFO for all we know and there would be no way to tell. Humming and a few planes could be almost anything.