Back pain is not necessarily related to the new crown booster shot. It is not normal to have low back pain after the third booster shot, and it may be an adverse reaction to the medication. Another need to rule out lumbar muscle strain, lumbar disc herniation and other diseases. The third shot of booster shot after the back pain, may be an adverse reaction to the drug, need to observe a period of time to see if the back pain disappears, if the symptoms disappear after a while is not a big problem, if the back pain may continue to have other conditions need to go to the hospital for examination in a timely manner. Lower back pain is not necessarily related to the strengthening injection, but also need to consider lumbar muscle strain, lumbar intervertebral disc herniation and other diseases may be. Lumbar muscle strain is mostly related to long-term bad posture habits, cold and other factors. Lumbar disc herniation may be related to poor posture, trauma and other factors. If the lumbar pain after the third booster injection does not improve, it is recommended to go to the hospital for further examination and treatment.