Why can't people try to understand?

I don't know what's wrong wtih people these days. I really hate this. No one understands how im trying hard for my exams and by that, it means not going out. In the holidays i tried to turn down peoples to study, but someone keeps making me say yes, but in fact i really cant, nor do i want to go. I tried saying no but then they keep saying dog etc, making me go. In the end i say maybe. But then again, they should try to understand that im trying to study and they think that one day without studying wouldnt affect, but to me it does. One day without studying makes me forget the work, waste time and get lectured by parents for not using my time properly and really i want to do well in my exams no matter what. It doesnt seem like im trying, but i am. I do feel like it is my fault for like not going with them, but i thought they could have hanged out with the bday girl who they know of. They don't need me. I just want to study. Is that bad to ask for? Do i have to ask permission to study? I said i would hang out with them perhaps at the gates. I have no other choice, its either go hang out or study. But of course everyone would rather study. I wanted to study. They didnt let me, complained to me and even in the holidays didnt really let me study.