scabs on my scalp

Hi, welcome to the ehealth forum and I am glad to help you.
You seem concerned about seborrheic dermatitis which is a common, inflammatory skin condition that causes flaky, white to yellowish scales to form on oily areas such as the scalp. Stress, fatigue, weather extremes, oily skin, infrequent shampoos or skin cleaning, use of lotions that contain alcohol, skin disorders (such as acne), or obesity may increase the risk. In general, symptoms of seborrheic dermatitis include skin lesions, Plaques over large area, greasy and oily areas of skin, Skin scales -- white and flaking or yellowish, oily, and adherent dandruff, Itching, mild redness and hair loss.
The diagnosis is based on the appearance and location of the skin lesions. You can treat flaking and dryness with over-the-counter dandruff or medicated shampoos. Active ingredients in these shampoos include salicylic acid, coal tar, zinc, resorcin, ketoconazole, or selenium. Shampoos or lotions containing selenium, ketoconazole, or corticosteroids may be prescribed for severe cases. To apply shampoos, part the hair into small sections, apply to a small area at a time and massage into the skin.
You must consult your dermatologist if seborrheic dermatitis symptoms do not respond to self-care or over-the-counter treatment and if patches of seborrheic dermatitis drain fluid or pus, form crusts, or become very red or painful.
Hope this helps. Take care.
Note: This post is not to emphasise final diagnosis as the same cannot be made online and is aimed just to provide medical information and no treatment suggested above be taken without face to face consultation with health care professional.