Why does Mr. Loomis criticize Ann

In Chapter 14, Mr. Loomis comes back to consciousness and tells Ann that he heard her playing the piano and reading to him in his delirium. After a few days, Mr. Loomis can sit up and feed himself. Ann finally feels safe returning to the fields. Mr. Loomis yells at her, though, for not getting to the planting sooner. Later, Mr. Loomis practices walking, but falls. However, Mr. Loomis will not allow Ann to help him rise.