Small pain in my chest by Michael Mack is a poem where the poet is trying to portray the psychological, emotional and physical agony of a soldier in a war.His pain when he loses his fellow soldiers/friends/mates in front of his own eyes.His anxiety regarding the consequences.Will he make it?Will he die today?Will he be able to see the faces of his family again?Will he be able to embrace his wife , mother,kids again? These things go over his mind when he is  at war along with the danger,strategies,etc. This poem is a very heart-touching and emotional one.Therefore, the title suits it perfectly.

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The poem deals with an incident where an American soldier sitting amidst the battle ground (surrounded by corpses) meets the narrator of the poem with a "small pain" in his chest as he was hit by a bullet. As the narrator gives him some water to drink, the soldier ponders over his pain which won't let him stand up on his own. He also thinks about his family (wife and mother) and what they will think  when they hear about this situation. And then he dies. Thus the title-"Small Pain In My Chest" is significant and appropiate,.