Hair Loss: A sign of aging?

Much of my hair has been dropping lately and even my mum has noticed that while sweeping my room. A scratch of my head could easily bring down 5 strangs of hair! Am I balding soon due to aging? Oh no... Or is it the food I eat? I don't eat too much salty food and I don't add MSG when I cook instant mee. Then what happen man? Or is it the side effect from the flu medicine prescibed by the doc? Or maybe it's the shampoo... What could it be? I don't think it's stress as I don't feel stressful (though I should be) Damn.