Questions about alopecia

Dear Dr. Redmond,

I am a 38 years old female from France. I used to have extremely thick hair. After the birth of my second child, 4,5 years ago, it started falling much more than usual, but since I had so much hair, it took me 3,5 years to realize that I was actually losing it. During this period, I sometimes had low ferritin level - last year only 14 - and I changed my birth control pill twice. Last year I only had the half of my usual hair, and now I maybe only have one third.

My scalp is in good condition, my hair is dry, and I don’t have acne or any other problem usually related to a high testosterone level, so I suppose that my hormones are OK.

I am taking iron food supplement, so my ferritin is now at 55. I am also taking vitamin B and zinc. Three months ago I started with Diane 35. All of this was prescribed by my dermatologist. Still, this last month I have been losing more hair than before. About a half of these fallen hairs are short, only 1,5-2 inches. Even though the volume of my whole hair has decreased dramatically, since February the scalp can be seen on the top of the head, around the parting.

I would like to ask you the following questions:

1. How long time does it take for iron and Diane 35 to make their effect? Can Diane be a cause of my increased hair loss during these last weeks?

2. How can I know if my problem is due to a telogen effluvium or if it is androgenetic alopecia? My dermatologist doesn’t seem to be sure.

3. How much hair can grow back with minoxidil, in case it works? (I haven't started yet.)

4. Could you please tell me how often do you see women in my condition growing back at least some of their hair? Can a hair loss really stop if it has lasted for years?

Thank you in advance for your patience with all these questions!
Sincerely, Alice