What does it mean to dream of wrecking a car to avoid hitting a black dog standing in the road?

I had a dream in which I was driving my car at night when I saw a big black dog standing in the middle of my lane. I swerved to avoid hitting the dog and while attempting to re-enter my lane of travel, the car veered off the road and started rolling. I woke up when I hit my head on something in the car while rolling. What could this mean?