Transmission acting up

I just had my friend replace the drivers side lower control arm. The next day, my transmision would hesitate when it was supposed to upshift and when I go to put it in reverse, it hesitates for a second and then slams into reverse. I got under the car to take a look and found a small 2-wire clip that my friend forgot to plug in that I had to push from the bottom upwards, located towards the wheel end of the control arm but that did nothing to fix my problem.