I am 23 years old i run and exercise regularly . I don't smoke nor drink. From past 4 days suddenly my breath goes away for a second and comes back while i stop running and sometime while running also it happens. It was happening before also ones a while but its happening day by day. I have done cholesterol test and urine test everything is normal. And a year before i have done eco and tNt test also it was also normal i don't have problem while i walk everything is good i experience no pain nothing. Any problem ?