RaceTrac

I went in the store prepaid $50 for some gas. I then walked away to gather some more items to purchase while im in the back of the store he yells at me about the person not pumping the gas. If im in the store how do I know that my girlfriend wasnt pumping the gas. Being embarrassed and upset I put the items I had in my hand back and left out the store. I will never comw there again and will tell all my friends and family how I was yelles at like I was a 5yr old and I'm 41..