2015 Nissan Rogue brakes problems

Wife was driving car and applied brakes. They didn't work right as the car did not slow as it should have. Rear ended a car that was stopped at light. Assured me 100% that she was applying brakes and that she wasn't texting or looking at phone. Accident occurred at or around 25 MPH into stopped car. Clean hit directly front end to rear end. Everyone walked away sore but relatively unscathed. Cars left via tow trucks. Next day wife was complaining of spots in eye and dizzy. Went to er. Nothing wrong supposedly.

I was in a small parking lot for a playground in wayland, ma. I was driving very slowly as kids can come out of nowhere. I found a spot to park on the left, so I turned my wheels and went in. To make a complete stop, I pressed on the brake. Suddenly the car accelerate, and go through the chain link fence, with the engine making a roaring sound. I immediately pushed harder on the brake, as the car went through the fence. The vehicle stopped when I pushed on the brake harder to the floor.