So what are these and why do they rile your characters so much? Do some of your characters handle the trials of life better than others and, if so, why and how? What would count as an irritation in your fictional world that here on our own planet might be seen as a catastrophe or something your characters shouldn't be wound up about at all?
Are the irritations you portray shared by other characters in your stories? Is there anything that the society/world you've created considers an irritation and how did it come to be seen this way? (There is always a reason for these things!). Answering all of these will help you flesh out your world and your characters better and that is always worth doing.