Maybe this is just my 12 years of California living that is talking now, but folks, if an earthquake is below a magnitude 5, its just a little shaking. Earthquake rattles northern Illinois:

A rare earthquake struck northern Illinois early Monday, rattling windows and awakening residents across several states.

No injuries were reported from the quake, which happened about 1:11 a.m. CDT.

Brian Lassige, a geophysicist with the U.S. Geological Survey in Colorado, said the quake was magnitude 4.5, and its epicenter was about eight miles northwest of Ottawa in northern Illinois, close to the village of Troy Grove.
...
"It was mayhem around here for a while," said Pattie Burke, a dispatcher for the Ottawa police. "We had more than 200 calls from residents in a short period of time, all of them wanting to know what had happened. A lot of them seemed to think a truck had crashed into their house.

Granted we don't get a lot of earthquakes out here in the midwest. From experience I can tell you this, just enjoy the ride, you'll know when it's time to worry.