I work in a lseep lab, and I am a registered sleep technologist, and I just want to share with you that one of the worst thing syou can do for your sleep is look at the computer or tv late at night or in th emiddle of the night.
The reason is, TV and computer screens Mimic daylight/sunlight-and that tells our body clock to be awake, instead of asleep.
If you do wake up, and can't go back to sleep, reading is a better choice, or listening to an audio book.
Also, if you are exercising too late at night, you may find it difficult to fall asleep or stay asleep.
I also find that Melatonin supplements truly help you fall asleep and stay asleep.
I hope that helps you!