I agree with everyone else in that you should see a specialist, and even start meds. I also think you should cut down your hair shorter, to a 2 guard or maybe even a 1, it'll look better that way...or, grow your hair to like 1 and 1/2 inch so you can get a better idea of your hairloss. Since you're thinning evenly all over you may be able to hide it better that way.
Family history of baldness?