Cough in teens: When to call
  Call 911 anytime you think you may need emergency care. For example, call if:
  - You have severe trouble breathing.
  
  Call your doctor now or seek immediate medical care if:
  - You cough up blood.
  - You have new or worse trouble breathing.
  - You have a new or higher fever.
  
 Watch closely for changes in your health, and be sure to contact your doctor if:
  - You cough more deeply or more often, especially if you notice more mucus or a change in the color of your mucus.
  - You have new symptoms, such as a sore throat, an earache, or sinus pain.
  - You do not get better as expected.