S8 Engine damage? Burning and clapping

I was on the highway the other night with a friend of mine, driving fast. Munich-Ingolstadt and back. When I, back in Munich, had taken the boyfriend home, I drove home normally, so calmly. I then speeded up for a moment, and when I went off the gas he ran really restless, so during the engine brake. I stopped right now, engine stopped. Cooling water ok, oil under minimum but stick down still moist. Before I left, I filled up the oil, so 160Km before. (?!) I immediately to the trunk, fetched oil, stuffed up and let 15 sec run. Engine shakes and shakes like Harry. Turn off the engine again, let it cool down. After 10 minutes, it started again, running completely normal in idle. A little speed increased, to hear funny rattles, but only all 2 sec, as if something were loose. Not with every crankshaft rotation. Engine off again immediately, ADAC called. After an hour, he shows up, he listens briefly and says, "There's something rattles." Great. During the waiting time I read out the error memory with the CAR PC, not a single error. No detonators or similar. ==References==
Today, however, I was with Audi and we ran it again for a short time, there was on cylinder 3 ignition oscillators in the error memory.
Oh yes, oil does not smell funny and is clean (oil change is not 2000Km ago), no warning lights have been applied and cooling water temp was also normal.
So, except for the rapidly falling oil level, everything is normal. But I could almost apologize for that, because I had a very heavy right foot, and that for a long time. 160 kilometers in 50 minutes. Besides, I did not fill up safely to maximum before leaving, but filled up from a third full without measuring afterwards about 0,3- 0,6l, I don't know exactly anymore. But there was certainly so much in it that it should not normally be empty after 160Km.
Otherwise, no noticeable smell, no oil loss.
Does anyone have an idea? Piston tipper?
Vince