Been in one too many of these, it often makes you question wether it's your fault, and that is very devastating. Though unknown to most people as soon a project is treated as a project and not your own product, its faith is decided by someone else.

You have no input on the stories, estimation and design decision. It's faith is no longer in your hands. They pull the wires, they decide. Hopefully their decision will be good and you'll do fine.