Any vomiting or diarrhea?Has she been urinating/defecating normally?Does she get bones, rawhides, or people food?Is her belly hard to the touch, or soft?
Has it been going on all day, or did it start about the time the storm started rolling in?Has she had problems with storms or noises in the past?
Thanks for answering my questions.
In the absence of any other symptoms, it's hard to know for sure what is going on with her. It's very possible that it's a combination of the storm coming and the new puppy being just too much for her to deal with at this point.
Since she doesn't have any outward symptoms, and because she's young (which essentially rules out things like cancers, underlying disease, ect), I think for tonight, you can just monitor her and see how she's doing in the morning. If she's still acting out of sorts in the morning, then she should see her vet, just to be on the safe side.
Hopefully it's nothing more serious than being emotionally overwhelmed with the oncoming storm and puppy.