Did you feel it or sleep through it?
A 4.5 magnitude aftershock shook the U.S. border in the Imperial Valley overnight and was felt by people in San Diego County.
The 2:12 a.m. quake was centered 16 miles west southwest of Calexico. There were no reports of any injuries or damage.
Some of our Facebook fans felt it.
“Definitely felt it, felt much larger than 4.4,” said Heidi Johnson.
Others woke up, but weren’t fully aware what was happening.
“Felt it in and out of dreaming. It was a weird feeling,” said Raffaele Antonio Scullari.
Hundreds of aftershocks have hit along the Laguna Salada Fault since Sunday's magnitude 7.2 earthquake, which killed two people in Mexicali and caused more than $100 million in damage in California.
Let us know if you felt it. Comment below, send us your thoughts via Twitter @nbcsandiego or add your comment to our Facebook Fan page.