Severe lower back pain, felt like lower back inflamed and warm to touch; This is a spontaneous report received from contactable reporter(s) (Consumer or other non HCP) from medical information team for a Pfizer sponsored program. The reporter is the patient.  A 19 year-old female patient received bnt162b2 (BNT162B2), administered in arm left, administration date 03Jan2022 (Lot number: FE3594, Expiration Date: Feb2022) at the age of 18 years as dose 3 (booster), single for covid-19 immunisation; influenza vaccine (FLU VACCINE VII), administration date 03Jan2022 (Batch/Lot number: unknown) as dose number unknown, single. The patient's relevant medical history and concomitant medications were not reported. Vaccination history included: Bnt162b2 (Vaccine Name: First Covid Vaccine, Lot Number / Expiry Date: ER8730, Route, Anatomical Location: left arm, No. of Previous Doses: No, Date: 30Mar2021), administration date: 30Mar2021, when the patient was 18 years old, for Covid-19 immunization; Bnt162b2 (Vaccine Name: Second Covid Vaccine, Lot Number / Expiry Date: ER8730, Route, Anatomical Location: left arm , No. of Previous Doses: one, Date: 20Apr2021), administration date: 20Apr2021, when the patient was 18 years old, for Covid-19 immunization. The following information was reported: BACK PAIN (non-serious) with onset 06Feb2022, outcome "recovering", described as "Severe lower back pain, felt like lower back inflamed and warm to touch". The event "severe lower back pain, felt like lower back inflamed and warm to touch" was evaluated at the physician office visit. Relevant laboratory tests and procedures are available in the appropriate section. No follow-up attempts are possible. No further information is expected.  Additional Information: The reporter wondered if a symptom could be possibly evaluated to see if its a side effect of the Pfizer booster vaccine. Recently she was boosted about a month ago and she began to experience severe lower back pain a few days later and it had not gone away even with chiropractic therapy. She highly believe that this was a symptom of the booster, she asked her chiropractor about it and he found it unusual because she was young and did not engage in heavy work. She reported that she is a healthy person, she got a physical and blood work and x-rays and it was all good.  She reported as soon as she got the booster dose she had a lot of back pain but it has toned down. She went to a chiropractor and they said it could be from the vaccine. She reported that her lower back is inflamed.   Follow-up (16Feb2022): This is a spontaneous follow-up report received from a contactable consumer. This 18-year-old female consumer (patient) reported that: Updated information included Ethnicity, Dosage regimens, vaccine information, vaccine facility information, HCP information, patient information, lab test, outcome of the event, onset date, Co-suspect drug. She reported that after booster, and later in report, She reported that she had her yearly Flu shot on a Flu vaccine on that same day and the same visit as getting her Covid vaccine, booster. She reported that probably 3 days after her vaccination on 03Jan2022 she experienced severe lower back pain, felt like lower back inflamed and warm to touch. She reported that she had an X-Ray, and was told by the doctor that nothing abnormal was noted. She reported that she was told that her spine was not straight. She reported that she wondered if the combination of the Covid shot and Flu shot caused her issues.  Follow-up (16Feb2022): This is a spontaneous follow-up report from a contactable consumer. This consumer reported that: Updated Information included: Phone number format updated in patient tab, Dose description updated in products tab.   Follow-Up (22Feb2022): Follow-up attempts are completed. No further information is expected.