OK, so it's been about a couple weeks since I noticed these bumps on the back of my neck. I only noticed them because I kept scratching and it wasn't long before I realized it would scab over but every time I showered, they cycle would begin. I try and think back to see if I changed anything in my routine as far as detergent or shampoo and I haven't. It was only recently that it formed a small patch at the base of my hairline on the back of my neck and it irritated it would puss and have this distinct odor. I originally thought it was dandruff but now I know better. What would have caused this?