Starter problems of the 2016 Mazda MAZDA6

I was braking to a stop after decellerating, driving originally about 45 mph. Traffic was stopped in front of me. I was in motion on a highway, going straight ahead. My car slowed but resisted stopping. I pressed on the brake pedal harder until I came to a complete stop. My right foot was entirely on the brake, as I only use my right foot to operate the pedals. The engine was revving like it was accellerating. The car was in drive. No warning lights came on the dash. The engine continued to rev higher in intensity. I put the car into park, and the engine revved much higher. I pushed the start/stop button to turn off the car. The warning lights came on the dash. I was able to roll down the power window even though the car was turned off. I tried to restart the car after about a minute. The starter engaged, but the car did not start. I tried twice again and it did the same thing. I tried a fourth time and it reacted as if the battery was almost dead, some sound but no movement. I couldn't put the car in neutral to have the attending police officer push it out of the lane of traffic, and we noticed the emergency brake was engaged. I did not engage the emergency brake myself! my husband arrived, and he and the officer were able to put the car in neutral, however, they were unable to disengage the emergency brake. The car had to be loaded onto a roll-off wrecker to be taken to the dealership.