Can't Sleep. HELP!!!

I slept in pretty late today (from about 2am-10:45am) without meaning to. I tried to make up for it by being active and avoiding sugar and caffeine, but I'm still wide awake after crawling into bed over 2 hours ago. I've been sick for the past few days, but I normally fall asleep quicker if I'm not feeling well. I've also taken extra melatonin supplements. I do feel a little drowsy, but no enough to fall asleep. To make matters worse, my anxiety is acting up and making my heart race, which doesn't help at all. What can I do?! I have a lot to do in the morning and I also have to work late.