Damn, 16 is a tough age to lose hair. Most people would be hesitant to recommend propecia at that age b ecause it could hinder your sexual development. it is really only for people who are 18 and older and even then some people take longer to sexually develop.
I would recommend using Minoxidil(Rogaine) twice a day to regrow some, and I would recommend buying Revivogen which is a dht inhibitor that you apply to your scalp. I would also use some Spironolactone 5% cream which you can get from minoxidil.com to take care of some of the testosterone and dht floating around. I would also use Nizoral 1% shampoo every 3 days which you can buy from a local supermarket or pharmacy for $15. I'd start on Propecia when you are 18 years old or when your doctor feels you are sexually developed. I would go to a Doctor to start with anyway. If he thinks it's safe for you then I say go for it- but I don't think he will at your age.
It really sucks that you are balding that early because it means you probably have a very aggressive case of male pattern baldness. What's your family's hair history like? Mother's side, Father's side? This would help
I also echo the previous poster who asked you to post pics. Pics of your entire scalp would be great. Take pics of your hairline with your hair combed all the way back so we can get a look at that. Also take pics of the front, top and back of your hair with it still combed back so we can get looks at that too. You can black your eyes and nose out for your privacy if you wish but pics would be great so we can determine how far along your hair loss is.
Good luck with whatever you decide.