15 and losing my hair? with picture

[moleman]

this might sound ridiculous but I'm 15 and I think I'm balding. Although the most obvious signs such as abnormal hair fall and bald patches on the crown etc have not begun to show I have recently noticed a definite receding hairline: http://i112.photobucket.com/albums/n...psee9b6655.jpg

This is also an increasing concern for me as my three older brothers have all got very thin hair with a receded hairline from around the age of 18. This trait was the same for all of my uncles on my mothers side however I share a different dad to my brothers but we share the same mum (could this mean I might not be coded to follow their pattern?). The strangest thing is, is that my mums dad has a complete full set of brown hair and he is 74!?
Therefore, should I really bother with products like propecia and roagaine? will they really help?
-Thanks, I am not the most confident of people and I would like to know what I can do before hairloss destroys the last scraps of my confidence!