The word "churn" means to move around violently, normally in a circular rotation. This does not mean the stomach is literally churning, but describes how the author feels. Alternate translation: "my insides ache" or "my stomach hurts" (See: [[rc://en/ta/man/translate/figs-metaphor]])
The author speaks of feeling grief in his inner being as if his inner body parts had fallen out of his body onto the ground. Alternate translation: "my entire inner being is in grief" (See: [[rc://en/ta/man/translate/figs-metaphor]])
This is a poetic name of Jerusalem, which is spoken of here as if it were a woman. Alternate translation: "my people" (See: [[rc://en/ta/man/translate/figs-metonymy]] and [[rc://en/ta/man/translate/figs-personification]])