Itchy scalp?

Hello,
So this is not lice. I had two people inspect my scalp.
But for the past two weeks my hair has gotten a little oily from not bieng washed for 5 days so I showered, waited 5 days, showered again, them waited another 5 days. 
Now I've showered again and my scalp is crazy itchy. I keep scratching mostly were my roots are right by my ears and back of head. No where else is itchy. I'm thinking maybe it's my pillow cases with too much dust mite buildup??