Can someone help me interpret this dream?

I have had a reoccuring dream off and on. It seems to involve me inside of a car and I am driving. I am going really really fast when I come upon a very steep hill. I jump the hill (like Dukes of Hazzard if you had to visualize) and I am really high up in the air. All of a sudden I realize gravity takes over and I begin to fall in the car but I never see myself fall. I have the feeling in my stomach like one would have when you ride a rollercoaster and you begin to ascend from the first hill! It is weird because jumping off of the hill seems fun, exciting, and scary but as I begin to fall, I get nervous, scared, that I cannot control or break my fall in the car. Can anyone help me shed some light on what this could mean and why I have it off and on. I had the dream a few months ago and have not had it since then.