Something that just happened

On my way home from work, driving down my usual route, I thought I saw someone approach the road in front of a business office that seemed to be closed with all the lights off. I swerved slightly towards the oncoming lane to avoid them. Curious, I checked my rearview mirror, but there was no one there. It was strange because there was a car behind me, lighting up the area, and I should have seen a shadow, but there wasn't. It was a peculiar experience.