If Thor’s hammer shot had landed, the situation would have been reversed and it would have taken multiple shots from the JLA to bring Thor down. Thor’s mistake was bravado. He chose to run through the heat vision as opposed to blocking it and that added to his wear.

Doomsday was killed by Superman’s final shot whereas Thor is temporarily KOed from the final shot of a Superman who is stronger than he was in DoS. So it does fit with what Superman clearly states. We do actually see Thor send Doomsday flying.

As you can see in the scan, Thor is already in a sitting position while Superman is being helped off of the ground. This indicates that Thor was up earlier.