Itchy Scalp With Or Without Red Bumps, Turns Hard, Tightens Up. What Is This ?

I got the itchy scalp with or without red bumps , eventually they turn hard skin and tightens up pulling the scalp after a day it reduces to swollen lymph nodes.I thought I must be allergic to shampoos but no other shampoo helped , tried putting lots of conditioner sometimes it works sometimes it wont . Antihistamine worked once when the itch was spreading on to the ear and neck , but surprise is that my dermatologist was thinking it is weird case that he don't know the answer ,although he wants to conduct skin test for allergens . What are those bumps and skin tightness .This is ongoing from 2009 for me .