I don't understand...
prior to Locke and Jack blowing open the hatch, Desmond (i think that's his name) was inside the hatch playing that weird music, right? Only after this does he see them through that mirror, I believe.
Yet, in the last episodes of this season, it reveals that Desmond was crying prior to this occuring, having just accidentally killed that guy and pressing the buttons after they went haywire, and wasn't playing that weird music.
Did I miss something?