Sleeping;not easy for me

                    Last night, i read a book and get to bed at 11 p.m, but I'm not fast asleep and my brain is  still going around about the book. I try to sleep.It doesn't work.So,i get up and turn on the lamp and pick up perodical written about Politics and economics. These are boring subjects for me;however, i think it can doze me off.I'm reading...reading...when i take a look at the clock,it shown 2:00 a.m. I'm yawning but i can sleep.  You think it doesn't strange,but not for me.It's my typical night. I haven't had insomnia. I feel that my body circle is wrong. I can't sleep until 2 or 2:30 am. Don't  you think I'm a light sleeper? No!! I'm not. I have a lie-in until 9:30 and sometimes almost 10:00 a.m. When I wake up early, I feel terrible; have got head-ache, isn't wide awake and then I get back to sleep again. If i had a work to do at early morning, I'm exhausted and frustrated.  I try to fix my body circle(biologic time) but is still happening to me.  I drink coffee every night,but I know it's not the problem. Before these days,I can fast asleep after drinking coffee, or not. I'm a postgraduate student and still learning . I living alone at a apartment. My parents support me to continue study. I read many articles written by sleep scientist. But I can't change my habit and can't fix it up. What should i do?