Not knowing exactly what they did my best educated guess would be that the idle is too high.
bollocks
Take it back to the shop and complain.
this is a typical problem with berettas, for some reason the bands in the transmission will not hold out after several miles are on the car, have the bands tightened or replaced, and you wont have any more problems
could be the motor mounts as to it jerking if its not the tranny..
if its a rear wheel drive you could have a u-joint going out.front wheel drive a drive axle going out one of your motor mounts are bad replace it....
check the trans fluid.
The problem could be the starter. It's tough to say without seeing the car. The best option would be to bring it to a mechanic, who could correctly diagnose the problem.
Took it to a car dealership and they found that the spark plug needed to be replaced. It is fine now.
The problem could be a mechanical problem it is important to take it to the mechanic to have it checked.
Could be low on Trany fluid or vacuum line is bad or off. Check both.Another answer:Depending on your transmission, it could also be a disconnected VSS or worn motor mounts. Trying to diagnose from a description is not always easy.
Trans problem
thats called "limp home mode" and its a very obvious sign you have something wrong with your tranny. you probably need a new one or to get the old one rebuilt