Inflammation is the most common reason for muscle pain and aches. Any time that major inflammation exists (strep throat, hepatitis, cancer, lupus, acute heart attack, etc.), signs and symptoms often include fevers, sweats, chills, fatigue, weight loss, and various muscle aches, pains and weakness.uscle pain and muscle tenderness, especially during periods of increased disease activity (flare), occur in as many as 50 percent of those with lupus. The symptoms may have different causes. It is important for your physician to determine the cause of your symptoms since treatments are quite varied.