Hi, The increased sensitiveness of lips can result from nutritional deficiencies(vitamin B)and dehydration, or over exposure to sun or cold and windy conditions.  Avoid licking the lips as saliva evaporates quickly resulting in them being drier than before. Drink plenty of water and take multivitamin supplements and do not apply cosmetic products for some days. Use a humidifier to moisturize the air in your home and apply shea butter or Vaseline on your lips. Eat foods high in calcium, magnesium and flaxseed oil.