AIO My mom took my Prom Dress and my Computer over a bad grade

sorry for any typing errors I’m typing this on my phone

I (16 f) and my mom (50 f) just got into a fight over my grade in my Honors Pre Calculus class. I have a 56% F and my mom is furious, but what really sent her over the edge is when I said that I hadn’t been doing my homework (which is neither a benefit or Detriment to my grade if I do it or not). she completely crashed out on me and told me to get my grade up or I wouldn’t be going to prom, and I wouldn’t get my computer back(despite me paying for half of it which she directly said). I tried to explain, but she said that she wouldn’t take any more of my bullshit excuses (IE my lack of attention because of my ADHD that she knows I have and refuses to medicate me for). I think she’s being completely unfair but I also know her standards and what she expects of me despite forcing me to take classes I’m too dumb for. And it’s not like she was an honor/AP student in high school either, she just expects me to be a wiz kid when I am anything but that. I have to know…Am I overreacting?

edit: wow ok was not expect so many of these. First of all my ADHD is newly diagnosed(3 months ago) So I’m still figuring out how to manage it. I understand her taking my computer. I spend way too much time on the thing, but my prom dress was my issue. Also I’ve slowly gotten back into doing my homework. In some districts in may be that you have to qualify for an honors course, but in my district that’s not how it works. I signed up for the course because she wasn’t letting me take the regular course. I consistently tell her that I struggle in honors math courses but she refuses to listen and thinks I’m complaining. I pay attention in class when my teacher teaches the material but I still don’t Understand it. My class doesn’t answer questions and because I’m scared of being judged I don’t either. I have a quiz today, I’ve studied, I caught up on my homework, if it comes back and improvement has been shown, I’ll delete this post and shut up, but if not I’ll keep it up.