To put it bluntly and in the most straight-forward sentence I can think of: this song is about rage. Because of all the stress to give in to all of these demands by the world and the people around him, all the stress in him is building up to rage and is slowly growing inside of him, causing him pain through these unstable and wild emotions that he is feeling. The rage is hurting himself more than anyone else.
To put it bluntly and in the most straight-forward sentence I can think of: this song is about rage. Because of all the stress to give in to all of these demands by the world and the people around him, all the stress in him is building up to rage and is slowly growing inside of him, causing him pain through these unstable and wild emotions that he is feeling. The rage is hurting himself more than anyone else.