Extreme hairfall. What could it be?

I have been experiencing a lot of hairfall for the past 2-3 years by now. If I run my fingers through my hair normally, around 2-3 strands fall off each time that I do it. 15-20 strands on running my fingers each time after oiling. I shed 200+ hair on oiling. Also, sometimes my scalp itches. The itching worsens at night sometimes and when I gently massage my fingers into my scalp so as to soothe it, I again experience a lot of hairfall. My mother forcefully shaved my hair last year because the volume had become 1/4th of what it used to be. Now it has grown upto my shoulders and I can see the hairfall problem occuring again. With this pace, I'll lose all my hair again soon and my parents don't take me to a good dermatologist. Please help me. What could it be? I am so worried.