To Whom This May Concern. I Am A 27 Year

To whom this may concern. I am a 27 year old female. When I do high intensity cardio my right ear will start to feel as if I'm getting a earache (dull felling) and it will last for a few days and will slowly subside. Also at times when I'm doing high intensity cardio my chest/lungs will feel cold and cause me to start coughing. This has been an on going issue since childhood. I have gone to an ENT doctor but they said their was no signs of any visible issues... I am kind of at a point of not knowing what to do now. I am a bikini competitor so I would like to be able to include HIIT cardio into my workouts but I can't until I can figure out what's wrong. Any suggestions?