Your problem my be due to generation of exces heat due to disturbed metabolism.
You need to improve your lifestyle. Eat on time. Have proper sleep on time. Avoid, outside, junkfood, Chinese, fermented foods, curd,poha,pickle.
Visit nearest ayurveda consultant, as you may need detoxification.
Till then it is suggested to take Nimbamrutasav 2 tsf with warm water after food and Avipattikar churna 1 tsf at night with warm water , Apply nilibhrungadi tailam for dandruff.