Did this mechanic mess my car up?

My brakes were sort of grinding before I took my car to the mechanic. So, once I took it to the mechanic and left it there with a trustworthy friend that worked there as well, I came back to pay the man and I drove my grandmother's car home while the friend drove the car home. Once I got home, I had to take my grandmother somewhere in her car. Bottom line is, I did not drive it until this morning. I got in at about 4:20 and pulled off at 4:22. Immediately I noticed that my car was jumping, I literally felt like I have hydrolics. And it jumped basically the whole way to the airport, but it got better as I drove. I thought it had stopped until I got on the freeway on the way home and it jumped uncontrollably and even the steering wheel was acting funny. What should I do?