It might be worth getting yourself checked out on the asthma front. I've had coughing experiences like you describe and apparently it is (at least) partly due to my asthma. Indeed I can give myself an asthma attack by laughing! The only way to stop that is to hold my breath; all the time I'm trying to breath in the asthma is reacting and closing down my airways. When I've held my breath for a few tens of seconds everything has relaxed and I can breath again.