Rapid heart rate with very light activity; feeling tired; After the second dose of the Pfizer Covid-19 vaccine, the Caller had complaints of mouth sensitivity, burning in the mouth from toothpaste that lasted two weeks (per agent), and feeling tired; After the second dose of the Pfizer Covid-19 vaccine, the Caller had complaints of mouth sensitivity, burning in the mouth from toothpaste that lasted two weeks (per agent), and feeling tired; sore arm; This is a spontaneous report received from contactable reporter(s) (Consumer or other non HCP) from medical information team. The reporter is the patient.  A 77 year-old female patient received bnt162b2 (BNT162B2), administered in arm left, administration date 04Mar2021 (Lot number: EM9810) at the age of 76 years as dose 2, single for covid-19 immunisation. Relevant medical history included: "Rapid heart rate" (unspecified if ongoing); "High cholesterol" (unspecified if ongoing); "moderate kidney disease" (unspecified if ongoing); "Osteoporosis" (unspecified if ongoing); "furry fruits" (unspecified if ongoing), notes: Especially with pineapple, peaches, apricot and strawberries; "nuts" (unspecified if ongoing); "sore in mouth" (unspecified if ongoing); "bladder frequency" (unspecified if ongoing). There were no concomitant medications. Vaccination history included: Bnt162b2 (First Dose: Received 11Feb2021, lot EL3249, Route, Anatomical Location: left shoulder), administration date: 11Feb2021, when the patient was 76 years old, for COVID-19 Immunization; Fluzone hd 65 plus (Vaccine Name:  Fluzone HD 65 plus , Lot Number: PF2021-22, Route, Anatomical Location: unknown, RX 812594, Store 15004 INJ 0.7 ml), administration date: 24Sep2021, when the patient was 77 years old, for Immunization. The following information was reported: FATIGUE (non-serious) with onset 05Mar2021, outcome "recovered" (05Mar2021), described as "feeling tired"; ORAL DISCOMFORT (non-serious), ORAL PAIN (non-serious) all with onset 05Mar2021, outcome "recovered with sequelae" (17Mar2021) and all described as "After the second dose of the Pfizer Covid-19 vaccine, the Caller had complaints of mouth sensitivity, burning in the mouth from toothpaste that lasted two weeks (per agent), and feeling tired"; HEART RATE INCREASED (non-serious) with onset 06Mar2021, outcome "recovered" (20Mar2021), described as "Rapid heart rate with very light activity"; PAIN IN EXTREMITY (non-serious) with onset Mar2021, outcome "recovered" (2021), described as "sore arm". Relevant laboratory tests and procedures are available in the appropriate section.  Additional information included: After the second dose of the Pfizer Covid-19 vaccine, the Reporter had complaints of mouth sensitivity, burning in the mouth from toothpaste that lasted two weeks (per agent), and feeling tired. Reporter states that she used 2-3 different toothpastes and after several weeks used one that was less reactive and the above complaints lessened. Reporter reported that after receiving the third dose of the Pfizer Covid-19 vaccine that she is having complaints of burning in her mouth from toothpaste, mouth sensitivity, and her upper lip is swollen and stiff. reporter reports that she usually has soreness with other vaccines. After the second dose the caller was very tired the next day and had a rapid heart rate with very light activity, it got up to 134 beats per minute. So far that hasn't happened with the third dose, the reporter's heart rate has gotten up to 120 and is lurking around 92 when she isn't really working out. This was higher than usual, the reporter usually was around 69-72 so this was a little bit of a rapid heart rate. Because the reporter had the rapid heartbeat after light activity for a few weeks after the second dose. The reporter saw her doctor for an EKG before the booster and it looks normal and so her doctor told her to get the booster. Reporter reported that she received Fluzone HD 65+ PF 2021-22 INJ 0.7ml on 24Sep2021 and had an EKG done before the booster dose of the Pfizer Covid-19 vaccine that was normal. Reporter was asking if taking antihistamines would help with her above complaints after receiving the booster dose of the Pfizer Covid-19 vaccine. The reporter stayed away from some of the toothpaste that caused the burning for a couple of weeks. The reporter was doing a puzzle and her heartrate was 134. The reporter had a sore arm after the second dose but was better because she did arm movements. The caller has very little soreness in her shoulder now. The reporter didn't feel it when she got the third dose of the vaccine and said "did you give it to me the man giving it said she didn't feel it because he was talking to her. The reporter walks 3 times a week and exercises 6 times a week. The reporter moved in her weights that she lifts at the gym from 6.6 to 10 pounds. The reporter rinsed her mouth after she brushed her teeth yesterday and thought that would take care of it. The reporter guesses some if it got absorbed because her upper lip was swollen this morning. The reporter's mouth isn't raw but her lip was worse. No emergency room and physician's office visit for adverse event. Expiry date was unknown.  Follow-up attempts completed. No further information expected.