Onward Hoe!

Man, I don't know what I ate yesterday, but given an incendiary device of any sort, I believe I could have created an impressive display of Chinese New Year-style pyrotechnics with the gas coming out of my body. I'm beginning to think maybe it was the milk on my cereal (but no, Marieke, I'm not becoming lactose intolerant). It tastes kind of...funny. The first two times I put it on my cereal, I had just brushed my teeth, so I thought that was the cause of the off taste. Then I thought it was the spoon or the cereal itself, but now that I've tasted it while eating two different cereals with several different spoons, I'm quite certain it's the milk. It tastes kind of sour and kind of metallic, but it's not expired, and it doesn't smell sour, so I don't know what the deal is. And apart from maybe giving me gas, it hasn't caused any digestive problems, so...hmmmm.

Alright internet search-masters, Google me this: What would make milk taste like that? And is it still safe to consume? Or am I slowly killing myself by ingesting it?