Costochondritis and Fibromyalgia - Could you be confusing them? Fibromyalgia causes widespread pain in the body’s muscles, tendons, and ligaments. While fibromyalgia primarily affects the muscles and soft tissues, it can also cause chest pain. Fibromyalgia also causes fatigue, sleep disturbances, and mood issues. Chest pain is a common symptom of fibromyalgia, and it can be a cause of concern for those who experience it. The chest pain associated with fibromyalgia is often described as sharp, st