Q: car not sounding and running properly

Most likely the loss of power after your oil change is just a coincidence. It is possible they checked your air filter and disconnected a sensor on accident. If this is the case, there should be a Check Engine Light on. If not, then it is most likely a coincidence that your car began acting up after you oil change. I am assuming you got an oil change because water is not changed with a filter of any kind, let alone an oil filter.

Your timing chain is most likely controlled by oil pressure, and since you just had an oil change, I would check your oil level. If could be low, but I would expect an oil light to be on if that was the case.

There could be quite a few possible failures with these sort of symptoms, so I recommend the following inspection of rough idling to be performed by a certified YourMechanic technician to help you figure this out. Good luck!