So, nothing to be concerned about, but imagine a giant walked up to your house and kicked it, once. That’s what it felt like. You panic after it’s over. It’s so quick that you don’t even fully realize it’s an earthquake until it’s gone (usually).
The cats looked up, peered at the back of the house, and then they were like, “whatever, 3.7”.
When it’s over 4, you really feel it. My first was a 4.5, I think.