Scalp question!

I know it is not the same exactly, but I noticed that I started developing dandruff and itchiness as a reaction from my hair dye. It was definitely a developed allergy, not something I had to start with and I had been using the same dye for at least a year. I wonder if it might be something like that for you as well?

Yeah, I agree with Dekilah that it could be a developed allergy to the products you were using.  If you switched to a new product & then it appeared after you used that for a while.  Have you tried using a very simple hypoallergenic/ sensitive skin shampoo? Have you started any new medications, supplements or using any new hair styling products/ anything that goes near your scalp or on your skin?  

I thought I had the exact same issue with what looked like pimples. I had them for a couple of months and couldn't figure out why.  I had switched BCPs and it turns out I was allergic to the new ones.  The "pimples" were actually hives. In my case I had hives scattered all over the body as well. I thought that I was also spontaneously getting body acne, insect bites, caught a little rash, & other little bump/welt causing conditions. For me, the hives started on my scalp and then moved down the body. It wasn't an immediate reaction or on a large scale so it wasn't obvious that they were hives.  Going off the meds cleared up the rxn & then after trying a couple other different ones with the same rxn, I just went back to the original.  

Long story short, I thought it was my shampoo & conditioner too but there is much more that you can also try to rule out as the cause.