What should you know about random shortness of breath?

Breathlessness may happen when the airways narrow, the lungs are inflamed, the heart cannot meet the body's demand, or the blood carries less oxygen. Asthma can cause episodes with wheezing or chest tightness; Acute Bronchitis may bring cough and chest discomfort. Anaemia can reduce oxygen delivery and cause tiredness. Angina may cause breathlessness with chest pressure, while Atrial Fibrillation can bring an irregular heartbeat. COPD and Bronchiectasis may cause recurring symptoms with cough or phlegm. Anaphylaxis can develop rapidly with swelling, hives, wheezing, or faintness.

Stop the activity, sit upright, loosen tight clothing, and breathe slowly. Note what you were doing, how quickly it began, how long it lasted, and whether cough, wheeze, fever, chest discomfort, palpitations, swelling, or dizziness occurred. Use a prescribed reliever exactly as directed. Arrange a clinical review if episodes recur, occur with ordinary activity, wake you at night, or are becoming more frequent. Avoid diagnosing the cause from the feeling alone.

Call emergency services for severe or rapidly worsening breathlessness, blue or grey lips, inability to speak normally, fainting, confusion, chest pressure, or sudden swelling of the lips, tongue, or throat. Urgent assessment is also needed when breathlessness follows a serious allergic exposure, starts suddenly with sharp chest pain, or occurs with a very fast or irregular heartbeat. Do not drive yourself if breathing is difficult.

Could this be related to my lungs, heart, blood count, medicines, or an allergy? Do I need breathing tests, heart checks, or blood tests? Which symptoms should prompt emergency action?