Here "smell" refer to his sores having a bad smell that is associated with rotting flesh. AT: "My wounds are infected and stink as they rot" (See: [[rc://en/ta/man/translate/figs-explicit]])
The pain of the writer's wounds have caused him to be bent over as if he were an old, feeble man. AT: "I am bent over in pain" (See: [[rc://en/ta/man/translate/figs-metaphor]])