I struggle to concentrate at mental tasks such as school work and driving lessons sometimes i just can't think about one thing and focus on it it's really annoying and i'm not very good a school work and over stuff like that?

There are psychologists at school that can help you with these issues. Go to your school counselor and request this intervention. You can be tested to see if you have a specific learning disability that can be treated. Best of luck to you!

Go to see your primary physician and let the doc take a history and do physical exam, order any tests that are appropriate, and make referrals accordingly. This is possibly related to Attention Deficit Hyperactivity Disorder. In the US specialists in neurology, psychiatry, neuropsychiatry and psychology are often consulted by the primary physician to obtain a definite diagnosis