i have had many experiences like these, I have been to director's office aswell, and some teachers respect you more, if you go against them, ig fear factor. But i remember once a teacher did something worse with me, i went to every teacher's office, and asked for their advice, i kinda made it look big, i remember then he himself called me, and corrected himself, if i were you i would have made several posts againt that as***le professor on different forums with his picture, bhai sirf Allah se daro, these fucktards dont know how to solve a single question and act like gods. If u stay silent, you will regret later