Stop and Shop complaint: Manager

When checking out i gave cash of 140.00. When register girl gave me change she said i gave her extra 20 dollars . We both were not sure about it so she asked Manager to check her draw . Register girl didnt want to short me and i didnt want to see her short. I realized when manager left to check her draw with the tele mate machine that i did give her extra . When manager returned we both told her that i did give her extra . Manager said to register girl with a snotty remark ( now she realized that) . Very disrespectful towards me. We all make mistake and i made one. The register girl wasnt sure either so i think we both did the right thing by having a manager check that draw. I am a manager of a retail store for over 15yrs . i know how to treat a customer either if they are wrong or right and not disrespect them as she did me . I would have never said what she did to the register girl infront of a customer. It seemed like it was a big bother for the Manager to count a draw because it disupted her social business with friends at the customer service desk.