Walmart - Pharmacy

I needed a prescription filled at Wal-Mart last night after work. So I dropped it off and the worker asked if I wanted all three filled, and asked if I was doing some shopping in the store or leaving. I said that I was leaving and when should I come back, in an hour, two? So she said to come back in two. So I left and came back in two hours. So there was a line as usual, so I waited for my turn, and a half hour later finally got to the cashier who then proceeds to tell me that they are just now filling it. I said you told me it would be two hours, so I waited two hours, then waited in line a half hour, now your telling me its not ready? Then the other filler, says mam its not our fault, everyone is waiting, and we are very busy. I said but my time is valuable too! Why didn't they just tell me three hours or come back tomorrow! Then I wouldn't have wasted my time and gas driving around. They really need a different system.