Hi Dear, Welcome to HCM. Understanding your concern. As per your query you have back pain with symptoms of flu which is because of upper respiratory tract infection leading to common cold, which can be caused by bacterial or viral infection. Need not to worry. I would suggest you to consult ENT specialist for proper examination. Doctor may order test like viral culture test , throat swab test and blood test to confirm the diagnosis and rule out causes. Doctor may prescribe antibacterial amoxicillin or anti viral acyclovir depending upon the diagnosis along with decongestants. you should take proper rest and drink plenty of fluids. You should take muscle relaxants as well. You should take steam inhalation along with vaporizers. Avoid hot, sharp , spicy food. You should do warm saline gargles and drink one spoon of honey mix with glass of lukewarm water. Hope your concern has been resolved. Get Well Soon. Best Wishes, Dr. Harry Maheshwari