Heart rate spiked fo 146.; Felt lightheaded/ Few days later  started feeling dizzy. Dizziness became very bad and its ongoing up to date.; Numbness and pressure on the back of head; Pressure on the back of head; felt like a fizz on the top of my head and a burning sensation felt like burned brain cells/ burninginside the rest of the day.; Started burning inside starting from my stomach going up, almost like a very bad heartburn; This is a spontaneous report from a non-contactable consumer, the patient. A 42-year-old female patient received an unknown dose of BNT162b2 (PFIZER-BIONTECH COVID-19 mRNA VACCINE; Lot Number: UNKNOWN) via an unspecified route of administration in the left arm on 24Mar2021 at 10:00 (at the age of 42-years-old) as a single dose for COVID-19 immunisation. Medical history included GERD, heart palpitations, disorder vestibular, dizziness (had a vestibular issue and dizziness past summer but haven't had an issue since August2020), penicillin allergy and seafood allergy (Crab). Prior to vaccination, it was unknown whether the patient was diagnosed with COVID-19. The patient did not receive any other vaccines within four weeks prior to the COVID-19 vaccine. Concomitant medications included metoprolol (MANUFACTURER UNKNOWN), famotidine (MANUFACTURER UNKNOWN) and esomeprazole (NEXIUM), multivitamins (MANUFACTURER UNKNOWN) all from an unknown date for an unspecified indication.  On 24Mar2021 at 10:05, the patient experienced within 5 minutes started burning inside starting from stomach going up, almost like a very bad heartburn. On the same day at 10:15, the patient experienced heart rate spiked to 146. Felt lightheaded, a numbness and pressure on the back of head and felt like a fizz on the top of head and a burning sensation, felt like burned brain cells. The heart rate went to normal after a few min. Felt lightheaded and like she was burning inside the rest of the day. On an unknown date in 2021, the patient experienced few days later started feeling dizzy. Dizziness became very bad and it was ongoing up to date. Patient stated that she had a vestibular issue and dizziness past summer but haven't had an issue since Aug2020. She also stated that it felt like the vaccine triggered it and she was still trying to recover a month later. The events resulted in doctor or other healthcare professional office/clinic visit. Therapeutic measures were not taken as a result of the events. On 24Mar2021, the patient underwent heart rate and the result was 146 (UNSPECIFIED UNITS). Since the vaccination, the patient had not been tested for COVID-19. The clinical outcome of the event heart rate spiked to 146 was recovered on 24Mar2021. Whereas, the clinical outcome of the events burning inside starting from stomach going up, almost like a very bad heartburn. Felt lightheaded, a numbness and pressure on the back of head and felt like a fizz on the top of head and a burning sensation, felt like burned brain cells. Felt lightheaded and like she was burning inside the rest of the day, few days later started feeling dizzy. Dizziness became very bad was recovering at the time of this report.   No follow-up attempts are needed; information about lot/batch number cannot be obtained.