Saigon-Hanoi-Saigon in 72 hours

I lost my passport a couple of days ago and in order to get a new one I need to go to the Embassy in Hanoi, not taking a flight. So I went for the (so they say) most comfortable and economic choice (I'm not so sure about the comfortable part though) I just discovered the "cell" I'm supposed to spend my next 27 hours in...