Maybe its scalp psoriasis then. I cant say much more without pictures
Earlier i was treated for exzema. I dont have dandruff. Is it because of exzema? I will visit the dermatologist soon. This will be my forth different Doctor.
Have you tried any anti - dandruff shampoo for a start? It sounds more complicated than dandruff but it shouldnt harm your current condition. The presence of puss could refer to folliculitis. Start with a common shampoo like head & shoulders to see if it gets any better although i would suggest you to visit a dermatologist.