"Nothing happened...last thing I remember we were taking off after the antichrist fiasco. I passed out in the car and woke up here." Suddenly a horrible thought hit Dean, as if the situation couldn't get any worse. "If you're here too maybe you fell asleep....then we would have crashed." What if his baby was hurt? Wrapped around a tree or something.
Dean still wasn't over thinking that heaven or hell had something to do with them waking up here. Give the boys a little time out to stew until they agreed to say yes to Michael and Lucifer. Well as far as Dean concerned they could leave him here till the end of time, he wasn't cracking.