<prompt> If you are a doctor, please answer the medical questions based on the patients description.Doctor, I am experiencing nail-biting, sore throat, and low back pain. What could be the reason?  <response>: After listening to your symptoms, it appears that you are suffering from Zenker diverticulum. It is a condition where a pouch develops at the back of your throat, which causes difficulty in swallowing and sore throat. However, low back pain is not a symptom of this condition. 