I think I been looking for an excuse to not take her to get her spayed because I don't want to leave her !
Better to leave her for less than a day, than risk her death. Pyometra is a very real, very serious disease. Ovarian/uterus cancer is common, and often deadly. And, because you can never be 100% sure, 100% careful 100% of the time ... what if she did get pregnant? What if it was a much bigger dog? What if she died having the puppies? Get her spayed, potentially save her life.