you may be maintaining consciousness through your efforts to force yourself into sleep.
This is counterproductive to the relaxed mode your mind/body must be in to actually go to sleep.
stop it is all i can say. Quit thinking. Literally. You'll be out like a light.
meditate before bed after a nice long bath and cup of warm marijuana milk with a shot of cinnamon in it
...quit drinking caffeine after the noon hour...mid day of whatever schedule it is you keep
Even though you may not feel hungry or thirsty, lack of good, healthy food or sufficient hydration can be enough to keep you awake as well.
try to make sure you get a healthy dinner at the very least, and make sure you are drinking plenty of water.
Stress on the body can lead to stress on the mind, which may in turn prevent you from sleeping when you most need it.