I have suffered long bouts of insomnia over the years and one prolonged session totally affected my mental health which necessated a Dr's visit and sleeping pills, never again !
I have read all the 'do's' and 'don't's' as I'm sure most have ? such as do not lay in bed awake ! get up and occupy yourself. I even got to the state where I would rise and go for a walk in the early hours of the morning. For what it's worth here are my thoughts
Simple fact 1, the more you worry about 'not sleeping' the harder it will be to sleep.
Simple fact 2, you almost certainly get more sleep than you think you do.
Simple fact 3, relax yourself, don't 'stress' about daily events and you will sleep, it is a natural bodily function and given the right conditions you will not be able to stay awake
When in bed, do not check the time, look at your phone etc, just set your alarm (if needed) checking the time is counter-productive ? leading to "Oh no it's 2.45am and I'm still awake"
If you are unable to 'get your head' in a relaxed place conducive to sleep read about
breathing exercises for stress.
Best of luck and sweet dreams