For the preparation of university entance exam(matric) i have been studying daily, for about 2 weeks i have lost sleep b/c i start studying from 5p.m-10p.m including the day time from 5a.m-11a.m and i start to sleep from 11a.m to 2p.m..... and my question does this sleep disorder can cause a serious disease b/c i am feeling upper back pain , and what do you advice me , what kind of studying method should to use inorder to decrease the side effect please help me.