Dr.......yes, the dermatologist can determine the "health" of your scalp...and analyze your family history. What you are experiencing could very well be inherited male baldness or thinning (sorry to have to say that).
I found out because of the type of surgery, removing cysts on my ovaries, put me in a mode like a woman who had a baby. After childbirth your hormones go back to normal and can cause a lot of hair shedding.
They really examined my scalp.....my gyn or family doctor didn't!!!
What a relief to have it grow back, but I had huge anxiety whenever I washed my hair. It is indeed a scary thing as a woman to see lots of hair come out!!!!!!!!!!!!!!!!
There are a lot of shampoos designed for thickening.....Nioxin is suppose to be the best in the market....
Spare yourself the anxiety...go see your dermatoligist and get some peace of mind.