The car stop in the middle of traffic

I have a scion Xa 2004 with 65000 miles. This morning, I was driving on the freeway where the car stop reacting. When I tried to press the gas paddle, the car is not accelerating, instead the car is slowing down in the middle of freeway. I rolled the car to the side of the freeway. Afterwards, a cop showed up and push my car to the closest shoulder where my car is in neutral position. When I tried to step on the brake paddle, it is not responding also. At last, I have to pull the hand break to stop the car. When the toll truck showed up, they charged my battery because when my car is pushed by the cop, the battery icon showed up on my dashboard. After they jumb my car, it works fine. The battery was replaced two weeks ago. During this weekend, I did a service where they replace the front and rear brake, 2 belts, flush the coolant, oil change, change the oil filter and air filter, change the spark plug.
What could be the caused of this problem? I am not sure what to do.