Achebe uses direct characterization to create Okonkwo's character and his personality. At the beginning of the book, we as the readers view Okonkwo as this strong, powerful man, we can see this in chapter 1 "He was tall and huge, and his bushy eyebrows and wide nose gave him a very severe look" (Achebe 3-4). Then throughout the rest of the book we see how be begins to break and "things fall apart" for him. When Ikemefuna is killed it really crushed him because even though he wasn't his real son he loved him very dearly and it was a great loss for him, and began to wish his daughter was a boy. We can see these mournful qualities at the beginning of chapter eight, "Okonkwo did not taste food for [2] days after the death of Ikemefuna. [...] he was so weak that his legs could hardly carry him" (Achebe 63).
https://prezi.com/mx7d5-6kr3lm/copy-of-things-fall-apart/
"Then something had given way inside him. It descended on him again, this feeling, when his father walked in, that night after killing Ikemefuna" (Achebe 62).