how do i know if i have asthma

The first step in diagnosing asthma is talking to your doctor about your symptoms and your health. This can provide clues as to whether asthma or something else is causing your symptoms. Your doctor will likely ask about your symptoms and your exposure to substances that have been linked to asthma. Questions might include:

What are your symptoms? When do they occur? What, if anything, seems to trigger them?
Are you often exposed to tobacco smoke, chemical fumes, dust or other airborne irritants?
Do you have hay fever or another allergic condition?
Do you have blood relatives with asthma, hay fever or other allergies?
What health problems do you have?
What medications or herbal supplements do you take?
What is your occupation?
Do you have pet birds, or do you raise pigeons?

Your doctor may:

Examine your nose, throat and upper airways.
Use a stethoscope to listen to your breathing. Wheezing — high-pitched whistling sounds when you breathe out — is one of the main signs of asthma.
Examine your skin for signs of allergic conditions such as eczema and hives.
Your doctor will want to know whether you have common signs and symptoms of asthma, such as:

Recurrent wheezing
Trouble breathing
Chest tightness
Symptoms that occur or worsen at night
Symptoms that are triggered by cold air, exercise or exposure to allergens.

In children, additional signs and symptoms may signal asthma. These may include:

Louder or faster than normal breathing. Newborns typically take 30 to 60 breaths a minute. Toddlers typically take 20 to 40 breaths a minute.
Frequent coughing or coughing that worsens after active play.
Coughing, clear mucus and a runny nose caused by hay fever.
Frequent missed school days.
Limited participation in physical activities