If you say 'She ran a mile' you risk giving the impression that she did run some distance (even allowing for the possibility that the distance was exaggerated). To put it another way, there is room for two sorts of exaggeration - action (she ran) and distance.
(At least, that's the way I hear it; I think I too would add the 'almost'.)
Another way of saying 'she was very surprised' - rather less polite - is 'she nearly had kittens'.
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