Me, a Good-for-Nothing Dragon

The protagonist transmigrates from Earth to another world and becomes the most powerful god there. But unable to control his divine power, he goes berserk and nearly wipes out every god in the universe. The other gods join forces to seal him away for a hundred billion years. When the seal is finally lifted, the protagonist has turned into a little dragoness. In the days that follow, she gradually regains her divine power.

Note: This is a gender-swap story, with the protagonist changing from male to female. There is no pretending to be weak while secretly being powerful: even as a little dragoness, she is still incredibly strong. However, using her full power always comes at a price.