Hi dear, Welcome to Healthcaremagic!
You are probably suffering from a condition known as keratosis pilaris
. In this, hair grows in skin & may cause red marks as described by you. Clinical pictures would have been useful. You may Ist start using some oil like coconut oil or olive oil on affected areas as you have a dry skin
. You may also use Retino A 0.05% cream locally at night ONLY. Good luck.