I recently put an accidental extra 4 quarts , and I know hear a low thump ie like a piston but the engine runs fine and there is no power loss, just a simple draining off the pan I hope. The engine runs fine just notice this small metallic rhythmic thump on acceleration , and deceleration.
If you have not done so, I would drain the oil back to the fill mark before trying to start the engine. I hope you have not damaged anything. Did it do that thumping before too much oil in it?
Too much oil will get foamed up and not flow as it should.
This may already be the cause of the sound you hear .
Get the excess out soon.
( NM elecrtic bassist )