Very interesting question. The story that Okonkwo remembers as he lays in bed I think could be seen as a kind of parable that has a lot to say about Okonkwo and his life and how he reacts to situations. Let us remind ourselves of what the story says, and as you read it, try and think how it could be symbolic:
Mosquito, she had said, had asked Ear to marry him, whereupon Ear fell on the floor in uncontrollable laughter. "How much longer do you think you will live?" she asked. "You are already a skeleton." Mosquito went away humiliated, and any time he passed her way he told Ear that he was still alive.
There is a sense in which this parable is about the danger of judging on appearances, as Ear did, and how Ear suffered as a result. If we transfer this situation to Okonkwo, we see that he is a character, who in his haste, bravado and desire to show himself to be a man, makes many hasty decisions without thinking them through, and suffers as a result. We most clearly see this when he is exiled, but also in his response to the missionaries who come.