It can be due to folliculitis. Folliculitis is the inflammation of one or more hair follicles. The condition may occur anywhere on the skin.
Folliculitis starts when hair follicles are damaged by friction from clothing or blockage of the follicle. In most cases of folliculitis, the damaged follicles are then infected with the bacteria Staphylococcus (staph).
It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.
Look up blogs/sites for demodex mites and morgellons. see if any of those people's symptoms seem the same as yours.
I believe what we all have is likely caused by Cheyletiella or Neocheyletiella mites. Likely from a rabbit, dog, or cat. I have struggled with these for three years now. Family thinks I'm making mountains out of molehills, and that i am overly sensitive. I've done so much research, i probably know more than most people would ever want to know about parasitic mites. It all started when my stepson's mother got an indoor pet rabbit as an "emotional support animal". I see the same white sand on my family members, my eyes feel like there is sand constantly being sprinkled in them, my skin is insanely dry, despite copious amounts of moisturizing, i feel them moving around my scalp an pinpricks all over, mostly my scalp, ears, nose, and lower legs and feet. I purchased a microscope to look at the "sand" and dry skin, and have found they are tiny light orange mites. The orange mites are hard to find as they are buried in loads of skin flakes, but after spraying myself and my dog with topical ivermectin (intended for cattle and sheep), you will find them. The ivermectin causes them to move which you can definately feel as it basically makes them unable to stop moving and thus eventually die. They eat keratin, which is in skin, hair and nails. I am now giving my dog oral iver mectin every week and she has much less itching and her extreme "dandruff" is receding. Her nails were crumbly, split and weak, but with treatment are much healthier and stronger and look more normal under the microscope. I also notice less sand in my eyes and ears, less pin prics and less itchiness myself. I have been treating her for 3 weeks so far, but it can take months of treatment to get rid of them. My biggest problem now is the constant re-infestation from my 12 year old stepson, who carries the mites into our house every week from his mother's apartment. The rabbit lives in his bedroom, sleeps under or on his bed at his mother's. She is in denial and threatened to not allow him to come stay with us when i alerted her to the possibility that her rabbit is probobly an asymptomatic carrier of these mites. There is A LOT of misinformation about these mites on the internet and with veterinarians. I have yet to find a vet that knows anything about these mites, been to three, but can't afford any more. This is one of the best articles i have found on the subject. Look up "what's eating you? Cheyletiella Mites" by HH Reynolds. There is a free pdf available from the Semantic Scholar website.
Sounds like scalp ringworm, tinea capitis...