Severe back pain lasting two weeks is most often due to muscle strain, poor posture, or a minor disc issue, but it needs proper care to prevent it from becoming chronic; try to stay gently active (avoid strict bed rest), use hot compresses to relax the muscles, maintain good posture while sitting and sleeping, and avoid heavy lifting or sudden movements. Simple stretching exercises and short walks can help with recovery, and you may take mild pain relief medication after consulting a doctor. Using a firm mattress and proper back support can also reduce strain. However, you should seek medical attention if the pain is not improving, is very severe, radiates to the legs, or is associated with numbness, weakness, fever, or loss of bladder/bowel control, as these may indicate a more serious problem.