Make sure the Current Time Indicator (ie, the playhead) is not at the last frame of the Comp ?
Also, if Shot_001 is not the Comp you want open, just double click the other one in the Project panel.
OMG how the f*ck did I miss that? Good lord I need to start sleeping more. Now I feel like such a n00b. Thanks for pointing that out though, it would have driven me nuts.
I can assure you it has happened to me. Probably more than once.
And wait until you get the "RAM preview needs 2 or more frames" message, which is a different version of the same disease
Been there... done that. Although I was sleeping better at that point in time so I noticed that sooner rather than later.