Shell review: very rude employee!!!

VERY RUDE employee (gave me the name John but was not wearing a badge) in the Delray Beach, FL Shell gas station. I approached the cashier with candy to purchase as well as an extra $20 bill. When he opened his register, I asked if I could have change back for the other $20 bill and he said "No. I dont have change, " and slammed his register (WHICH WAS FULL OF CHANGE). I politely put the candy in which I had purchased in my purse, grabbed more candy, and went back to the register. He REDUSED to ring me up! He YELLED, "This is not a bank! If you want change, go to the bank." I just stood there. He began to take the customers behind me as I stood there for 10 minutes! Another employee walked in (named Jerry who had a name tag), i explained to him what had happened and he informed me that there was nothing that he could do about it but he would ring me up because he was about to take over the shift. But before he could do it, a CUSTOMER who had saw this whole thing take place, came in and gave me change. I told the sales associate that he was very rude and i will be speaking with his manager! This was horrible customer service at this location. This shell gas station (off atlantic ave & military trail) is by my job and I go here all the time but NOT anymore! I will also be informing my coworkers of this situation and they will not be coming here either! That RUDE ASSOCIATE needs to be addressed and I will be speaking to his manager on Monday when he comes in. If this is not addressed, i will report this company to the BBB.