Sharing Our Innermost Thoughts

Maybe I am overthinking this. Maybe I am avoiding facing these harsh feelings because I might have to scrap the past and just recall everything and cringe.
So basically, I used to go to this math class ever since I was in middle school, and the math teacher was pretty strict rock up.
Not to brag or anything, I worked really hard in grade 10 and scored pretty well in maths and my overall percentage was also pretty impressive as well and he admired me for my efforts. So I dropped maths in 11th grade and I came back in 2021, after an entire year of pandemic! I was excited to start fresh and well because it is my board year.
But guess what, the pandemic happened and I was on house arrest for the longest time. I wasn’t keeping mentally well despite all the resources and my grades really sunk. My mother being furious called the maths teacher (who was the head of the institution) and told him about my marks in chemistry.
After some time, I heard from somewhere that he said a couple of mean things about me and my parents and I was furious when I heard this. I couldn’t even say anything to him and I hate him for saying that.
I was doubtful of sharing this and I still am but I don’t know how to process this
He is very arrogant