McDonald's

I purchased a vanilla milk shake that had orange and brown liquid covering 40 percent of the shake. It looked like it was contaminated with something. I asked the clerk about it and she told me it was normal it was syrup. I took pictures of the shake, while on the McDonald's counter with the lid on and off. I couldn't force myself to eat it so I threw it out. The clerk wouldn't offer me another shake nor my money back. The manager called me later and said the problem was fixed with the shake machine, but didn't address the lack of service by the clerk until I forced the issue. I do not trust this McDonalds.