My Math Class

I have a D in my math class. I dislike this class very much. It's Math II. I'm a freshman, so that means it's the higher up level for that class. The normal class would have been Math I, but I did that last year. I finished last year with a C- in that class. I practically begged the counselors of my high school to let me be in Math I again, since I struggled so much in it in 8th grade year. They wouldn't let me. So now I'm about to fail math II, all because this stupid school wouldn't let me go to a lower level. I hate this school, i miss middle school. I hope I can get a good grade on the final. Because this school has semesters, not block schedules, I have to remember everything I did in Math all the way back in August. It's currently December. I forgot everything from August - October. And, what's worse, is the grading scale is insane. The assignments are worth 15% of my grade, and the tests and quizzes are worth 85% of my grade. How can anyone pass this class? I'm struggling to keep it together here. The only reason my grade is so low, is because I failed a test in week 2 that didn't get entered into the grade book until week 10. That's exactly 8 weeks later, which is 2 months. My moron teacher never catches up on grading work. She's always late, so then I have no idea as to what my grade actually is. Right now, she still has to enter a test we took 2 weeks ago. I literally go to tutoring after school and everything, but nothing works. I even pray, but that doesn't work either. If i fail this class, I'm in big trouble. My mom said that if i fail, she'll take away my phone for a month. And, she said, since I won't be having my phone, i can't go anywhere with my friends because there will be no way to contact me while i'm out. She also said she'll be taking stuff from my room, stuff that I like. She specifically mentioned my books. The books that I BOUGHT, with MY OWN MONEY. And, she said she'll be giving me a long list of chores every day. I actually hate this so much. I wish i didn't go to this school. And, if i fail this class, i have to retake it in either the summer or junior year. I'm going to kill myself