Bullying is a skill, they often know just how far to go without getting punished and that people who retaliate are often the only ones who get blamed.

I'd escalate the situation and say I got attacked by whoever threw something at you. If they don't do anything about it, you can bring the police into it. I know that's a severe escalation for just throwing things at you, but assault is assault. You can even press charges for assault. IDK if any of that would stick, but having the police called on them may make them think twice before they bully you again. Plus if brought to the attention of teachers and they don't do anything, you can totally threaten to sue. It's America, you can sue for just about anything. But allowing you to get attacked in class and punishing you for not even physically retaliating, yup, I'd make sure to use the word "attacked" I mean... I'm a pushover and don't like confrontation, so I probably wouldn't do that, but I'm sure you could.

Unfortunately teachers and principals in America despite “zero tolerance policies” are bad at recognizing and punishing bullying. I still have a scar on my had from when I reached up to grab something someone was poking me with in shop class that turned out to be a metal tape measure. The kid pulled it back slicing my hand. In many instances if you do anything about it, the teacher who was there the whole time will blame you. (And in another instance did) Really, I think a few lawsuits per district may be necessary to enact changes, and would totally sue if the same things happen to my kid now. I would 100% settle for no money and systemic guarantees that the district and school would actually change.

I'd have thrown that teacher into a wall.

That’s awful and I feel so bad for you OP. Every school I’ve ever been to always says “0 bullying policy” yet I got bullied at nearly all of them, sometimes (not often though) by teachers too. Life gets better OP I promise you this.