Are you sure you are getting enough Armour? Are you feeling back to normal other than your hair? (Most people need at least 120-180mg.)
Also, it could just be a shedding time for you. When I switched to Armour, it was in the fall, and my hair quit falling out.... but this summer it has been shedding quite a bit. (Not as much as before Armour though.)
It will also take longer than 4 months to notice a difference. How fast does hair grow? 1/4 inch a month or something?