I think that there will be different answers here. One of the most distinct feelings experienced is an intense sadness. The boy dies entangled in barbed wire that he saw as a fairytale-like obstacle to be overcome. His death is a direct result of his parents' fear. The ending is brutally painful. One of my feelings is a profound sadness at the parental fear of safety that chokes the life out of their beloved child. The child dies because of his parents' fear of "the other." It's emotionally brutal to think about how the parents end up killing what they sought to protect. In this way, Gordimer has illuminated an aspect of modern tragedy. The desire to create is equally tempered with the reality of destruction. This leaves the reader feeling hollow. Though the rest of the story is framed like a fairytale, the boy's death at the end is bleakly realistic and modern. Through this technique, Gordimer leaves the reader feeling empty.
People's feelings will differ in any work like this. However, I felt that one of the most definable feelings was a sense of true emptiness in seeing how fear ends up becoming its own self-fulfilling prophecy. I felt an emotional void. The child's death is a logical extension of a very human fear and paranoia about "the other."