2. Coughing up Mucus
Along with a cough that is persistent is coughing up mucus. The mucus will likely be green or yellow in color, which is a sign of an infection. At times, when coughing up mucus, you may notice that there is some blood in it as well.
This is a definite sign that something is wrong and you should consult with your doctor about your persistent cough and mention that there has been blood in the mucus you have been coughing up as well. It is likely that the doctor will listen to your lungs and possibly order an x-ray to determine whether or not pneumonia is present.