Hmmm...I wonder if something outside spooked her, and it just took a little while for her to realize that she was safe

Whatever it was, I'm glad that she snapped out of it for you. It's so scary when they act "not themselves". Mine both freak out if it rains

Luna wants to he held and Izzy just wants to sit on my feet

I try not to baby them too much, afraid to encourage the fear, but how can I just ignore them when they are both shaking so hard

?
If she does it again, it might not be a bad idea to see the vet, in case she's in some kind of pain. These little ones sure do keep us guessing