According to the news report

here

and here

We had an earthquake in the St.Louis area this morning! I was awake, but I certainly didn’t seem to feel anything…I guess I am not sensitive enough to feel the earth moving (though I have felt earlier tremors in Kolkata, and Bangalore, when usually people didn’t believe me!)

Well, since the Richter scale is exponential, 3.9 is nothing much…thank goodness…it’s nice to be able to read of such events in the news, and not have to experience them firsthand.