I'm so sorry I never thought to warn you, but some teachers are just like that. And it's college, so they can do as they like. I have a friend whose teacher didn't like her because of one comment just like that, something that she meant in a neutral manner and the teacher took it negatively, and for the rest of the year, the teacher gave her lower grades for mistakes in her papers that simply didn't exist.

My advice is to either apologize a lot, or switch to a different class and attempt to never see that teacher again. It's unfair, I know, but it's just the way it is. At the best, you have the hostility of the teacher. At the worst, the teacher will give you lower grades just because he can and he doesn't like you. I'm serious about this, it's just not a good situation for you right now. I'm sorry you had to find out like this. Not all teachers are bastards.