I had almost the exact same thing happen to one of my Mystery Snails! When we found her she had fallen onto the floor and rolled under the dresser. Thankfully she was completely unharmed, and also started moving around again after a few hours of me thinking she was dead. Mystery Snails can last a surprising amount of time outside the water; they're tough little guys!
Kindness and respect should be shown to all animals, no matter if they are furry, scaly, big, or small. Be a hero to the animals and GO VEGAN!