I am the same way! Except on the weekend I still wake up by 9. I tend to nap for 30 at lunch time, and sometimes if I am able to, I sleep after work for hours... but even when I don't sleep after work, I still can't fall asleep. My internal clock is all over the place. I think I am going to have to start using some melatonin or something... I feel you!!!!!
Yes you are not alone. In general people who tend to feel sleepy after midnight can have a condition called delayed sleep phase syndrome where one's circadian rhythm is shifted to the early morning. Treatment for this condition is with bright light in the morning (30 min to 2 hours) and good sleep hygiene (avoid light prior to bedtime). Please talk to a medical professional if this is causing a concern for you.