I been going through a lot of personal matters and i am in a serious situation sometimes i can't sleep.do this mean i have a mental problem?

Stress: If this problem is affecting you so badly, see a psychologist for counseling and further help. All the best.

It suggests: That you are under a lot of stress which in itself can lead to insomnia. But it's possible depending on any other associated symptoms and how long they have been going on you could have a complicating mood and/or anxiety disorder.

No, just can't sleep: When we go through tough times, we often ponder those tough times during our quiet times, such as when we're lying down at night to sleep. Thinking about things at that time keeps your brain active, which prevents you from falling asleep. It's normal, not indicative of a mental problem.