acts like it "double brakes" constantly

I'm not real sure of the exact date this problem began, but it was about one week after purchasing the car used. I contacted the salesman who was worthless to speak with after leaving his location. Finally the service manager contacted me, and requested that I bring the car in and he would ride with me. He noticed the braking issue along with the transmission issue (which I have not written a complaint about yet). He stated that the car needed to stay with them for a few days and his service repair manager would be working on it. Well I get the vehicle back, and within a week the transmission issue begins again. I call the issue with the brakes as "double braking". When stopping the brakes seem like and feel like they "double brake", once when I brake and a second time braking by themselves. Very annoying and uncomfortable feeling, wondering if the car is going to brake or not. The resolution I desire for this problem and the others I am having with the car, is TAKE THE CAR BACK. I DO NOT feel safe driving it, and I feel awful when I have to take my grandkids in the car....very unsafe feeling, very stressful feeling when driving this car. Do not buy a 2013 Chrysler 200 at any time. They are rated BELOW AVERAGE. I wish I had known this BEFORE wasting so much money on it.