Two possible solutions:
1. Learn some deep breathing techniques, and use them to quiet that racing mind down.
2. Like other people on the list, I read. Use a nightlight to read something familiar or slightly boring. that will keep your mind occupied without causing you to think.
3. Find some restful music (probably something classical) that you like and listen to that.
DON’T check your email, smartphone, ipad, or whatever for at least half an hour before you go to bed. The light that electronic devices give off affects the brain to make you stay awake.
And don’t worry about it so much. Lots of people have minor problems like that. The whole idea that if you’re “normal” you don’t have any problems or quirks at all was invented by the people who sell pills.