I have facing difficulties also at some nights trying to sleep. Sometimes I drink milk and it works. But sometimes I'm more awake than before because it makes me feel full and I can't sleep when my digestion is working. If I'm not mistaken, it's also not healthy to sleep after you consume food. I have tried different ways, like doing yoga before sleep, using earplug, changing my bed in different direction. I found that all this strategy have the same goal, which is to shut down your mind. There is one simple way I like to do now:
1. Relax the muscles in your face, including tongue, jaw and the muscles around the eyes. Close your eyes and lying.
2. Drop your shoulders as far down as theyll go.
3. Take a deeep breath until your lung's full, and release it until it completely empty. Do it slowly. Repeat 4 times.
4. On the fourth time, after taking a breath, hold it and count to 4. Then release it like pushing it out. And then repeat step 3.
I did this twice, and just flow with the rhythm. At least it help me to empty my mind.