Oh heck, talk about delayed update. Ed has many issues but I picked the most obvious one. FMA isn't mine
The Why of...Edward
Some people can't take a harmless comment and Edward Elric is not one of them. Perhaps harmless isn't the best word to use for anyone with stature issues will find being called small an insult. Edward is perhaps more prone to violent outbursts than most but his pride is far greater than most.
Had you simply commented that he looked small for his age you would certainly knowabout it. Edward hears things that are not said so a simple observation can turn into frightful insults in his mind. But would you believe its not actually his height he is all that sore about. Edward has taken on much responsibility and he is smarter than most his age but his height does him no justice. He has the mind of an adult in the body of a teenager. Anyone worth their salt feels hurt or offended when their skills or talent are put to question on appearence alone.
Perhaps this does not justify his terrible temper or his out-bursts of violence but he knows people are used to it now. He has almost allowed his temper to continue the way it has because it makes Edward...Edward. That little body can expell a rather large burst of emotion so if he can't be tall he will damn well be noticed!
Secretly, but don't let it be known, Edward realises girls exist...he just has too much to do to care too much. But on the odd occasion his brother is set upon by girls thinking that Al is the Fullmetal Alchemist, Edward notices. Female attention does not ever come his way without a small look of pity, bar Winry who just teases him for being small. That he can cope with, but the looks of pity for someone his age being so small is more than the alchemist can handle. He is a State Alchemist, part of the military, he has suffered much in his young life but all anybody can ever pick up on is his lack of height and two false limbs.