That's odd. I just proved that there is no sumo wrestler in my fridge by merely opening the door and looking inside.
You falsified a positive claim. That is the purpose of testing and verification. If I claim that God doesn't exist how do you falsify that? ... Right, by demonstrating that God exists. Good luck on falsifying my claim that God doesn't exist. I will look forward to meeting God next time I open my refrigerator door :)
I can't prove that God doesn't exist. I can't prove a negative. It can only be disproved. Do you see the difference?