every dog is different, we've had one that was scared, but mum hoovers up so often now, our boy is completely desensitised to it
to the point where you can nudge him with it running and he still won't move unless you tell him

and it's a full size dyson so it's not exactly quiet!
if you reassure your pup, she may well never like the hoover (who would? i blooming hate the sound of the things)
but eventually she may realise that it's not anything to be worried about.
as she can get away to a "safe" area now, this will likely be what she does all the time when you clean up with it