How to fix this hair problem?

When ever I comb my hair, play with my hair, wash my hair, dozens of hairs fall everywhere. Sitting at the computer right now, i can scratch my head, and about dozen hairs will fall depending on how vigorously i scratch. How can I fix this? I know it's not normal because my hair line is further back then the normal 16 year old boy. Umm.. what else? I dont colour my hair, I do have a lot of dandruff, and my parents dont wanna take me to the doctor because this isn't something life-threatening.