The cerebellum is part of the hindbrain in vertebrates. It lies between the brainstem and cerebrum in humans and helps regulate motor movements, helps us perceive senses and coordinates voluntary movements like posture and balance.
If the narrator was an injured woman, it would be "Sara sees red". If the narrator is Sara, it would be "I see red".
This passage has a melancholic mood. You can tell this due to some specific key words: "dull", "dark", "soundless." They all have a negative connotation. The imagery of a lone rider in a dreary and dull country under the oppressive sky may clue you in that the overall passage has a sad tone to it. Even later in the passage the author states that the scene is melancholic.
