Why is my 93 Pontiac Bonneville spuddering?

Hello, I have posted a question before, but I would like to get more answers. I have a 93 pontiac bonneville and the other day while I was driving, while I was driving, I noticed that the car was moving slow. I heard a pop noise, then when I tried to press the brakes, it was hard where I couldn't do it. The power went out in the car. I tried to start it up and it started right back up! I don't know what this could be. Some say a sensor, some say a tune up. And when I start the car, it keeps doing this spuddering thing. I just tried to start the car up again, and it was really making this spuddering/putt noise. Any suggestions? I am kind of scared to drive it to the shop, so I will get it towed. I just want to know if others have experience the same thing. There is gas in the car. Serious replies only. Thanks for your help.