While the film features a lot of drama and danger, including a fight between Davy Jones and the entire pirate council, the ultimate outcome does not involve the end of the world.
The ending of "At World's End" sees the destruction of the Flying Dutchman and the release of Davy Jones' soul, which restores balance to the seas. While some pirates are lost and the seas are in a state of chaos, this is not presented as the end of the world.
Perhaps you're thinking of another scene or film? Could you provide more context about what you remember?