injustice in school? Need advices asaaaap

okay so i need help with something, my school has this thing where at the beginning of the school year they send reports of your attitude/grades/efforts to your parents. Anyways I received mine today and in p.e it's written that I'm in danger of failing and doesn't put efforts but waiiit plot twist; my best friend and I did the same exact things, we both haven't been to p.e class in WEEKS and while we were there all we did was sit on a bench and watch everyone else because we refused to go into the pool but yet on her report it says that she has the average grade and is doing okay?? WE LITERALLY DID THE SAME THINGS! I find this really annoying and I want to go complain but idk if I'll seem like I'm overreacting

update; yes I do know that I deserve that grade for not participating and it's not the problem for me, the problem is why does my friend has a better grade when we both never participated? That's what make no sense to me, she should have the same grade as me because there's absolutely no difference in what we did in this class.