fist dose on 21Dec2020, second dose on 07Jan2021; pain and stiffness radiating from injection site all the way down arm,into breast, and middle of back; pain and stiffness radiating from injection site all the way down arm,into breast, and middle of back; pain and stiffness radiating from injection site all the way down arm,into breast, and middle of back; Started having chills; Severe headache; collapsed on the way back to bathroom and was unable to get up for about 20 minutes; tachycardia; extremely fatigued entire day; This is a spontaneous report from a contactable Pharmacist who reported for herself. A 30-year-old female patient received her second dose of BNT162B2 (Pfizer/ BioNTech Covid-19 vaccine, lot number Ej1685) at a single dose at 09:45 AM 07Jan2021 at left arm for Covid-19 immunization in a hospital. The patient had her first dose of Pifzer Covid-19 vaccine on 21Dec2020 at 12:00 PM at left arm, and experienced very mild reactions which included mild pain at injection site and runny nose/sneezing day after vaccine. The paitent had a medical hisotry of rash to penicillin as a child. Concomitant medications were not reported. The patient did not receive any other vaccines within 4 weeks prior to her first dose of Pfizer COVID vaccine. In the evening of second vaccine (around 17:00), pain and stiffness radiated from injection site all the way down arm, into breast, and middle of back. She started having chills. Around 10 hours after dose chills became somewhat violent despite being under 4 blankets. Severe headache also started. In the middle of the night to go to bathroom, she collapsed on the way back and was unable to get up for about 20 minutes. She also suffered from tachycardia overnight. her baseline heart rate runs in 60s- 70s, but was in 110s-120s (based on Apple Watch monitoring). Day after vaccine, she was extremely fatigue entire day and spent all but a few hours in bed. Arm pain mostly gone. Headache was very strong and persistent through the day. On second night chills not as bad but still occurred overnight. HR still elevated in 80s overnight. Morning of day 2 still had headache and fatigue. The patient did not receive any treatment for the events. The outcome of collapse and unable to get up for 20minutes, pain and stiffness radiating from injection site all the way down arm,into breast, and middle of back was resolved, chills and tachycardia was resolving, headache, fatigue was not resolved. Prior to vaccination, the patient was not diagnosed with COVID-19. Since the vaccination, the patient has not been tested for COVID-19. The reporter considered that the events was non-serious.; Sender's Comments: Based on a chronological temporal association and known BNT162B2 vaccine safety profile, causality between events fainting, violent chills and severe headache and BNT162B2 ((Pfizer/ BioNTech Covid-19 vaccine) cannot be completely excluded. The case will be reevaluated should additional information become available. The impact of this report on the benefit/risk profile of the Pfizer product is evaluated as part of Pfizer procedures for safety evaluation, including the review and analysis of aggregate data for adverse events. Any safety concern identified as part of this review, as well as any appropriate action in response, will be promptly notified to Regulatory Authorities, Ethics Committees and Investigators, as appropriate.