I am 26 years old, an healthy person, doing weight lifting, yoga,moderate running. But suddenly after a swimming session, I felt difficulty in breathing since past two days. I consulted an mbbs Dr. who did ecg, blood sugar, blood pressure, spo2 and xray test. But everything was normal. Bt pulse is around 60 which is low I think. I do not and other issue apart from shortening of breaths. What could be reason for this? It started after swimming.