Brake Loud Noise problems of the 2012 Ford Mustang

I turned right at traffic signal into a merge lane and accelerated to approximately 45 mph and merged left. At this point the car started jerking and making a loud noise. I placed my foot on the brake petal and could feel the brakes being activated, the car lost power and continued the jerking for approximately 200 yard. Other cars behind me began blowing their horns. I do believe some of the dash light came on but at the time I was concerned about staying on the road and was not looking too closely at the dash. The second incidence was on Jan. 16, 2014. All this was reported to the Ford dealer. They were unable to duplicate the incident and offered no help.