On-going Scalp/Hair problem!?

Hi, so you might have seen some of my posts about hair and scalp before.

Ok so next week I'm going to see a Trichologist about my scalp to see what the problem is. For about nearly 2 years now I've been losing my hair :( . I'm only 19 by the way. I went to the doctors about one year ago and he said it was jus due to genetics and there was nothing I could really do about it :/

I've got very thick hair and on the sides and back but an receding hairline and thinning at the crown and through the middle. I've lost a lot of confidence from this I really look a mess! :( But on my scalp when I touch it I can feel hard skin patches up there. Whenever I massage my scalp or brush my hair, always afterwards their are dry white/silvery flakes in my hair. Sometimes they are almost a scabby colour like a dark red. I noticed the other day I had a little sort of cut on my scalp but I don't know how it had got their. I've also got this other little spot which is a random scab that has just stayed their for a long time now. I also seem to have a lot of dry skin on my forehead after washing my hair and on my eyebrows. Could this be some sort of infection that is causing me to loose my hair overtime? Or is this due to fate and genetics lol? I saw this thing called Seborrhoeic Dermatitis and it maybe could be a mild version of that? It's defintley not dandruff though as I never have it falling down the back of my neck or something like that and it's never itchy. Does anyone have any ideas or maybe you've experienced what I've got? Thanks very much for your help!