general problems of the 2005 Volvo S40

As I accelerated to pass another car the overdrive got stuck. Even as I hit the brakes the car didn't stop. I put it in neutral and it started making a sound as if something was holding it back and would not stop. After approximately 5 minutes of hitting the brakes the overdrive finally let go. I called the Volvo and told them about the incident and they said it must be the computer and that I should just take the car to get it fixed. This could have caused a serious accident and even death. What is worse I had my granddaughter, who is just a toddler, in the back seat.