Some guy was ill and was sitting in a hospital room. He had a cell phone so he decided to call someone. After the converstation he clicked off and then heard a rumbling sound coming from down the hall and glanced over in time to see an orderly passing by with a load of boxes. That ordinary sight produced an extraordinary reaction in him. It came together in a neat little box all its own.

1. I understand that "hall" is the same as "corridor". So he spotted an orderly passing by at the other end of the hospital hall (corridor)?

2. The 2nd sentence is a bit puzzling. First he says that the orderly had a load of boxes and then that it came in a little box. Or maybe all the boxes were small and they came together in a bit bigger, but still a small box. But what the phrase "all its own" mean?

1-- Yes.
2-- The reaction he had 'came in its own little box'. It was a sort of epiphany.
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So this is a kind of metaphor.

He saw loads of boxes and then everything in his head accumulated (came together) in a sort of little box.

So the phrase "all its own" means "in his own"?
No, it means to and of itself: its (the reaction's) own box.
Ok, thanks. But this "little box" is a strange term to me.
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