The selling experience itself as smooth and I ended up buying an awesome pair of jeans. My concern is with the red associate who checked me out. She seemed very sad and not ok. 
She told me what my payout was going to be and with the jeans I was purchasing, (the jeans cost more than what I receiving for a payout), I would be getting (an amount) of money back. I corrected her saying I would owe money and we went gently back and forth a few times until she used the register and then said, “my bad” you owe ($7.06). 
When I paid her (cash), I gave her $10.06, and she gave me $3.94 in return. I told her she overpaid me, I only get $3 back and her reply was, “this is what the register says”. She was not rude, so please know I’m not angry or upset. I’m concerned. I wanted to go back to the store and ask her if she was ok, but I felt it would come off condescending and not as I intended, which was from genuine concern. 
It did not seem like it was just about math, rather something else was going on. I just hope she’s ok. 