1. Earth has been more seismologically active in the past 15 years or so,
4. There are about 500,000 earthquakes a year around the world, as detected by sensitive instruments. About 100,000 of those can be felt, and 100 or so cause damage each year. Each year the southern California area alone experiences about 10,000 earthquakes, most of them not felt by people.
OMG did you just feel that???? Oh God...
I don't think about that stuff