Come on, it's not the end of the world, it's a Delivery Date Estimator. It's intended or implied to have a margin of error. Your date of delivery went from 11/26, to 11/28, to 11/30? I don't mean to sound insensitive, but it's not like they said date of delivery should be 11/26, and then you finally get the car on April 1st. Like others said, step away from it briefly, catch your bearings, and do something fun and productive. Then, when you get the call from the dealer saying the car is there, prepped, and ready for pickup, go reward yourself.
As far as the loan is concerned, my credit union granted a 30 day extension within 10 seconds after I phoned them. Get yourself another lender. If that doesn't work, ask MB Financial what they will offer (their offer beat my credit union's by a quarter point, so I ultimately went with MB).