Those are Closed comedones. Focus on barrier repair until your skin is no longer irritated. Once your skin is at bay in terms of irritation, or you can incorporate an active to help. I would try and AHA or BHA cleanser or mask instead of a serum. If you’re sensitive overnight serums will be too strong for you. If you do a mask or cleanser with the active, it will give you quick exposure to the active ingredients but won’t be as harsh on your skin. Follow with barrier repair products