Scared of disappointing parents + GCSEs

I haven’t done any easter revision yet because I have been sick, and I literally missed the last 2 weeks of school because I had like 3 infections. I’m better now, and I am ready to revise but I just feel so down because my mocks were not that great. It’s bad to compare but all my friends were getting 70-80% while I was stuck with 50%, and all their grades were 9s while mine were 6/7s. I’m so disappointed, and my parents are as well. That should motivate me to revise but honestly it’s just made me so upset and I feel like all the revision I did didn’t even pay off. I feel so bad because I feel like I really am disappointing my parents, who invested so much into me and I’m struggling so bad, all my friends with 9s never had any tutoring and yet my parents put so much effort into me and I’m such a failure. Every time I try to do some work it just makes me want to cry, and those weeks I missed off school they ended up finishing the poetry anthology and I have so much to catch up on it’s overwhelming. My school also is stressing me out, because we haven’t even finished all the topics for the sciences, and my art book is literally empty because my art teacher never tells us what’s going on. I really don’t know what to do anymore, I really wanted 8/9s but with my current 6/7s it feels impossible