Sounds like she's just having a bit of a dig around.
Dwarfies love digging, if she does this alot maybe give her a deeper layer of shavings so she can have a proper dig.
My Todd's a proper little burrower, I swear he's part mole! I give him a layer of shavings about 7 -8 inches deep with some Carefresh sprinkled on top. He loves making little tunnels and then sleeping in them under the shavings. I never know where he is! lol