There's no point in trying to understand the sudden change in the way he treats you. Whatever his issue is, he does sound like a complete d*ck, and you had every right to say what you said to him. It doesn't sound like you went crazy or anything. You simply stated a few choice facts with outward calm. It doesn't matter if your inner calm was MIA for a moment. You got it back. Just think about all the people in the world who throw regular loud wobblies without cause! I think you were well within your rights to speak up in this situation. If it still upsets you, you can flip him a quiet bird every now and then from afar if it makes you feel better. I do it all the time to my partner when he's being a d*ck and he's not looking. Even though he can't see it, it makes me feel a bit better and just the act of doing it usually makes me crack up. Instant relief!