I made a mistake. I drove 60 miles with the low oil light on. When I got to my destination, I had the oil refilled. It was well below the min line, but still registering on the dip stick.

When I returned to the car a few hours later, it did not start. Apparently, the battery was flat, so we jump started it successfully.

While driving home, I very quickly noticed that the general noise of the engine was a lot lower than it should be. It sounded like the engine wasn't running as fast as the rev-meter (no idea what I should call that) showed. It was much worse at low speeds.

Is this problem likely to be because of the oil or am I talking about two or three separate things? Have I killed it?

FYI, I'm driving an old Mercedes (F reg), automatic transmission.

Thanks for any help you can give me.