Although she is probably fine, I would suggest a visit to the vet. She could have a minor physical problem that is causing this change.
What does she do when she goes outside? Is it possible that she thinks she needs to potty but doesn't? Could have a urinary tract problem--stone or infection. Or a tummy probem. Or maybe a sprain in her leg(s) or something like that.
Anyhow, I would say better safe than sorry and take her to the vet. Probably she is fine, but, best to know |