Has anything happened, like her nails being trimmed too close? Or maybe they were 'pulled' a little when last clipped? That can so easily happen as their nails are darned tough to clip. What I would do is take it very easily with her and click/treat her. Start with just handling her paws, no cutting, then work up, even if you have to do just one nail - click/treat and leave for a while. Maybe even a play between each nail. Sounds like you have to get her to realize that nail cutting isn't torture but fun.