You have hypothyroid so problem of dry thinned hairs and hair fall will be their so continue with treatment for hypothyroid and get regular checkup and follow up with endocrinologist. White hairs at your age is becoming common problem due use of chemicals products for hairs such as shampoo and conditioner so start using it less for now and consult a dermatologist too for further advice
Next Steps
Continue with hypothyroid treatment and see a dermatologist
Health Tips
Use vitamins B6 40 mg twice a day for two to three months take green leafy vegetables and fruits more often.