Speed Control Springs problems of the 2008 Toyota Sienna

We drove from pembroke to north carolina, taking a few breaks in between two weeks ago. We pulled into a service station to use the rest rooms and purchase cold drinks, in roanke springs, nc. My wife pulled into a handicapped parking spot in front of the store. She was only 10 feet from stopping the vehicle when the car accelerated forward and fortunately crashed into a concrete pillar otherwise we would have gone directly into the store. The surge of the car accelerating pushed me back into my seat, passenger. Our vehicle Toyota Sienna struck the concrete pillar directly in the middle of the front end. I then reached down and turned the car off. We were traveling with another couple, they had parked their car and heard the squeal of the brakes being applied and then the crash of our vehicle into the concrete pillar. The car is being repaired in roanke springs, nc at the bones Toyota dealer. We then rented a vehicle and continued our trip to florida.