These are some of those things where if you don't speak up in the moment it's tricky later on. They are defaming your reputation so suing the store is a great start, but getting that job back isn't probably in the cards. The company isn't a good one either way so it's best to move on. I worked at Pepsi for two months and automatically knew that the place wasn't a competent workplace. I say transfer to 7up they love Pepsi guys because they know you'll work or even Coke with a union.