What Is The Treatment For Severe Hair Loss?

hi doctor !!!
i am 21 yr old and surfing from hair fall since last year... my hair was very very nice....every keep saying that you hair look nice !!! but since last year my hair start falling so fast..none of my family is bald..even my father have good hairs....now he is 50 yr old..and now his starts falling but very slow...as a age factor...but my!!! at just 21st!!! plz help me...