'O' level science(biology)

i really think no matter how hard i study, stuff can't get into my stupid brain and stay there. i don't think i did well for the science bio paper today. wtf, i can't even do well for science, am i stupid or what? the damn Os are killing me, tomorrow is another killer subject- literature. the highest i have ever scored for lit was 25/50 and highest for social studies was 25/50 as well, how the hell am i suppose to take combined humanities? just hope the Os end soon, then i'm going to heck care everything until february when we get our results. i'm studying human geography now,nothing's going in, the words are just running through my head. right now to me, they're nothing more than words. i feel bloody stressed right now and she's angry at me. argh...............