Perhaps she doesn't like the shirt. Take it off. Unless there is a medical reason why you need to dress your dog, just don't do it. Some find wearing clothes uncomfortable. It's a dog not a doll.
I put a puppy shirt on my puppy for the very first time now she is acting super weird. Why??
How would you feel if you went outside
undressed? Now think of that in reverse.
That's how your dog feels.