Your question seems very interesting , because you can analyze it from two view points.
first why do people are so sensitive, you can say it is a trend or you can say that humans must be sensitive if they wish to get a long and create a civilization.
you can even say they eat to much spicy food and that makes them agitated (which surly contributes to over sensing ). there are many valid answers to your question.
But the seconed view point is just as intersting to look at.
Why do you specifically perceive your human surrounding as very sensitive.
Are you around a sensetive crowed ?
Or are you sensitive enough ?
I guess that the answer to your question might be somewhere between these two view points, analyzing your surroundings and yourself and you might reach an answer.
