spoilage of any kind rarely makes anyone sick and generally just spoils the food.
Spoilage bacteria is different than food borne illness bacteria like listeria, salmonella, e coli, etc.
EDIT: what makes you think it was spoiled?? If it tasted good it wasn't spoiled at all. That date means nothing except before that date, the product will maybe taste fresher, thats all. the date has absolutely nothing to do with spoilage.
Let me ask you this: if the date was next week but the milk tasted sour and nasty, would you drink it anyway becuase of the date? Of course not. So why would you not drink it if it tastes good because of the date.