I cant get off my computer...help?

From the start of kindergarten all I do is go on the computer and do nothing else. It has caused my marks to drop to a failing grade and made me very unsocial with the real world. Everyday after school all I can think about is playing on the computer, even when I have something important to do (study for Exam's, Projects). I tried to stay away from my laptop, but for some reason I make these excuses to myself that I need my laptop for researching or typing, however I always end up playing on my laptop for some reason. I ask advice from my friends and parents however due to my lack of social skills they get confused and say that I am just rambling nonsense. So I ask you what am I supposed to do.