What to do if i cannot fall asleep at night when ever i try to i over think and stress out and can't fall asleep for hours?

Give yourself a : Set time each day that you are allowed to ruminate about issues and get stressed. You can train yourself to do this. Don't allow yourself to try to work out problems or fret anytime near bedtime. Use of breathing exercises ; deep muscle relaxation will also help. Take care.

Consider hypnosis: If you are concerned about insomnia you should learn about hypnotherapy. It is something anyone can learn, takes just a session or two and can cure insomnia without using medication at all. It also reduces stress. Find a qualified psychologist to help you learn how hypnosis can help.