DD (7) had 'flu at start of year and complained of tight chest and finding it hard to breath. Since then she has occasionally said the same thing but I hadn't thought much of it (thought it was a no-school excuse as she has had friend problems), until we went on holiday a couple of weeks ago.
Nearly every time we went in the swimming pool she would complain of a tight chest and finding it a bit hard to breath. Once she said it was her throat and chest and she lay down in the shade for over an hour very quietly. After that we kept a closer eye on her and limited time at the pool.
She mentions feeling tight chested mostly in the evenings and mornings, but has no cough or wheeze. She has very mild ezcema.