Why am I coughing so much if all of the tests showed I'm fine?

Depends. .. on which test were done? Potential causes of persistent cough are too many to discuss here. Medication side effect is often overlooked. Persistent post nasal drip (allergy or non-allergy related), acid reflux, asthma, or vocal cord lesion are common causes that may occur with normal lab results (if not "looking" in the right direction).

Related Questions

Why am I coughing so much if all of the tests showed I'm fine?

Complicated. Most cough studies show that a chronic cough is often caused by more than one cause and thus the difficulty in establishing a cause. The most common causes for chronic cough are (a) post-nasal drip from hay fever or sinusitis (upper airway cough syndrome) (b) cough variant asthma or asthma (c) Acid reflux. Did you have a normal lung function test and chest Xray? Read more...
Not all about tests. A diagnosis of the cause of a chronic cough should not only be with tests. You should see a physician who listens to a full history and does a complete physical examination. The 3 most common reasons for a chronic cough are asthma, rhinitis, and gastroesophageal reflux. Tests can be normal in all 3. Please see someone or set up an appt with a HealthTap physician. Read more...