I feel so bad again :'(

I feel like crying. Ughhh. Reason? Studies. Seriously. I am really getting disappointed with myself when I get low marks. I have been thinking that my brain is slowly degrading. I don't know why. I don't feel that I am as smart now compared before. I'm really upset. What if I'll get line of 7 in the card? That would be a shame. I better start being serious with my studies now and ask help from other people so I can easily understand the lessons well. Just like in Physics, I am a bit confused. Especially in Chemistry, wherein I can't even understand a thing. I pity myself. Oh. Also Biotechnology. I get low scores on my quizzes. Wait, that's all sciences right? To tell you honestly, I never liked science. I hate myself. How can I cope up with the lessons well now? Ugghhh. Sorry teachers. Sorry mother. I don't know. Please classmates, help me. :(((( I really want to cry. I always get stressed. Huhu.