It drizzled most of the day so everything was wet and the road looked pitch black with no reflection from my headlights. The fog was just thick enough to make the trees on the side of the road barely visible.
As I drove down the road, my headlights would light up creepy looking branches hanging close to the road, or catch a discarded reflector or something else that lit up brightly. I kept seeing movement in the woods as I'd drive by, but it was only the reflection off of wet trees farther from the road. I got jumpy and tensed up, waiting for something to dart out onto the road in front of me. Whenever I realized I was holding my breath, I would relax and slowly exhale and let my heart rate return to a slower beat.
When I reached the driveway, I let out a little nervous giggle for allowing myself to get spooked like that.