Please Help Me Diagnose My Hair Condition?

My hair has been Falling for more than 4 months and its color has been changing from black (dark) to yellowish and its become very greasy specially when i dont wash it , I took 2 medical shampoos for 4 weeks and lamisil tablets , but the problem hasnt been solved . So Do i have seborrhoeic dermatitis or tinea capitis or what ? , i think my doctor is an idiot , how can i know which condition i have ? My hair continue to falling, changing its color , greasy

No doctor answers yet