:salamext:
Don't worry, your na an old man yet, so its got a chance to grow back insha'Allaah.
So its proli to do with your diet, like a deficiency in vitaminz. You proli got a shortage in iron, zinc etc.
Iron - lots of meats; Chicken, tuna, turkey, chicken liver and stuff like that - i think mainly meats. Spinach also helps out alot insha'Allaah.
Zinc - (if you don't have the right amount, u can get hair loss) - good food sources include beans, nuts, certain seafood, whole grains, fortified breakfast cereals, and dairy products.
You can check this link out for more info. about what vitamins you may need, and which type of people need them, and in what foods you can find them.
http://ods.od.nih.gov/Health_Informa...ct_Sheets.aspx
Also remember to cut back from using the gel or the brylcream, or the hairspray. These are most likely to mess your hair up bad. Instead, get some olive oil (not too much) and rub it in your hair before you go sleep, and when you wake up - wash it out, and do this for abit, you'll realise the benefits soon insha'Allaah.
Remember the most powerful weapon is dua' though, so don't give up hope insha'Allaah. Its only a test from Allaah azawajal.
wa Allaahu ta'aala a'lam. (and Allaah Almighty knows best.)
:wasalamex