I took my dog to the groomer?

he was rubbing his butt on the carpet, so I thought it was time to express her gland. the groomer said it was too full. After one day she started again rubbing her butt on the carpet. I give her heartworm regularly. she is an adult Yorki. I give her one greenie a day and the color of her pee has become green, but it is good for her teeth. could that be the reason she rubs her butt on the carpet? thanks.