Exam sick!!!

In the afternoon, i will be having my first paper on Robust Design. Till now i still not very sure what am i studying.... oh no.... this sem, really bad, i cant focus and i think i have become more n more stupid.... i cant understand what i reading... i really have no ideas why like that.... is it because of all the lack of sleep due to work?

My whole body are so aching.... i cant really sit for long. if i do that, i will be in the current condition i am in now.... whole body in pain. it has worsten due to me carrying notebook everywhere for 7days.... the bag was really heavy, cant stand it anymore....

how, in a few hour are my paper, i still feeling empty in my mind... =(