My bunny Sammy hasn’t come out of her xpen habitat since we moved in with my folks, because it is an all tile floor. She used to run around on the wall-wall carpeting in my former apartments. She just absolutely won’t set foot onto tile – not even the kitchen floors in my apts. So I understand that kind of a change. I am taking her (she doesn’t like to be picked up either) into our dining area that has an area rug now for a bit of exercise. However, she often ran for a short time and then curled up in favorite spots on the rug in previous homes, so it’s not as unusual a behavior as I thought at first.
You just need to be sure your bunny is getting the exercise she needs. Keep taking her out to play. Try placing a towel or blanket down across the floor she won’t step on if it can be a bridge to the rug she likes. (Don’t invest in any runner yet. It didn’t work for Sammy, but another member had luck with the idea.)
Definitely watch for eating/poo changes, as well as grinding teeth and hunching in a meat loaf position. She may be getting sick if there is a problem with these indicators. And definitely take her out in early morning and early evening. It’s their natural grazing time, so she’s more alert.