Mallard disturbed

I inadvertently scuttled a mallard duck sitting on a nest of eggs on Sunday. I was about to finish off some ivy clearance where previously I had pulled some thick ivy away from the wall of an outbuilding. The nest was built resting on the ivy ledge I had created. She flew away at the point where I was just a couple of feet away. I have no idea whether one disturbance will lead to an abandonment but I am staying away from the area in the hope that she has returned.