Certainly, by definition, asthma is a disease of altered breathing. This is manifested by narrowed airways. These narrowed airways are caused by inflammation in the airways and by airway constriction which leads to wheezing.

If you have difficulty breathing, you should see your doctor for evaluation.

'Improper breathing' where the patient has difficulty in breathing and breathes audibly with a fast respiratory rate is a distinct symptom of asthma. Classically the 3 symptoms of asthma include shortness of breath, wheezing (audible sound of breathing) and cough. Some patients might present with only cough or some only with wheezing or breathlessness.
It has to be remembered, however that symptoms can be present only during episodes (or attacks) of asthma even though subsequently they might be present in between the attacks as well. Typically there are known irritants to triggering of these episodes of breathlessness like smoke, dust, fumes, allergens etc. in certain circumstances do they advance is present episodically only in many patients and over time can advance into a stage of asthma where the patient has breathlessness even in between the attacks.
Anyone with a 'improper breathing' needs evaluation for the cause of the alteration of the normal pattern.