Laying the dishwasher on it side should not have done any thing to it to make it start making the noise.
There might have been a piece of glass or something laying off to the side and when you tip it over it found it way to the pump.
Take the spray arm off and remove the eight screw holding the housing on.
Remove the wash impeller. This is a normal right hand thread the trick is to hold the impeller to get it out.
Remove the four screw in the wash housing.
Work your way down to the drain impeller and remove any debris that you find.
There are two ball that are suppose to be there.
The drain impeller is likely seized on so don't try to take it off.
Reassembly in the reverse order and try running a cycle to see if the noise is gone.
Here is a link to the parts of your dishwasher model 66517822000 |