Dont worry it just happens sometimes...with me too.....you need to get more fresh air and get out of stress and tensions. Try to be near nature more. That would help!
Hey there,
This is just your feeling, take it out.
If you want comfortable & nice sleep try out listening some soft music, Meditation music too. Such kind of music makes you feel relaxed & stress free.
Make a habit of reading books, & read before you go to sleep. When you start reading automatically you will feel like sleeping. Also you can keep the slice of Cucumber as well on eyes. It provides coolness to your eyes & make you feel relaxed.
Have some water or keep a water bottle near you bed :)
I read somewhere that if you feel like you are forgetting something, it's water.
Hope that will fix it! :)