Hair turning from straight to curly. Me!

Hello doctors i still remember my hair were straight and normal but from last 6-7 years i noticed they becoming rough, frizzy and curly. I don't what did this and also i am experiencing hair fall because of curly and rough oil. Changing shampoo and oil doesn't worked. Tried aloe vera too but it worked for only few days. If i am applying coconut oil before shampoo i noticed less hair fall and bit managed hair. I don't what exactly.the problem is but i feel there is something wrong with my shampoo. Changing to new helps for few days only. So please advice me for good shampoo according to my hair condition. Please i am requesting to those doctors who asks for online consultation or physical visit you please stay away. I need someone who can really help.me Thanking you.