"I" am also experiencing what feels like possible vertigo.; "I" keep getting dizzy. "I" feel off balance and when "I"  turn "my" head the room starts to spin.; "I" feel off balance and when "I" turn my head the room starts to spin.; " I" am still experiencing these events and some nausea; "I" missed two days of work because "my" symptoms have been so severe and "I" have been feeling so weak.; "My" arm also has a large, hot, red circle where "I" took "my" shot.; "My" arm also has a large, hot, red circle where "I" took "my" shot.; "I" vomited profusely the night after "I" got "my" second shot for about fourteen hours straight. "I" was unable to keep down food or water until late Wednesday afternoon (around 16:00); "I" have had diarrhea on and off since "my" shot; "I" have had headaches nearly constantly since "my" second dose.; This is a spontaneous report from a contactable consumer, the patient. A 26-year-old non-pregnant female patient received the second dose of BNT162b2 (PFIZER-BIONTECH COVID-19 mRNA VACCINE; Lot Number: ER8734) via an unspecified route of administration in the arm left on 13Apr2021 at 11:30 (at the age of 26-years-old) as a single dose for COVID-19 immunisation. Medical history included body mass index (BMI- 34.6) and polycystic ovarian syndrome (PCOS). Prior to vaccination, the patient was not diagnosed with COVID-19. The patient did not receive any other vaccines within four weeks prior to the vaccination. Concomitant medications included metformin (MANUFACTURER UNKNOWN), multivitamin (unspecified) and spironolactone (MANUFACTURER UNKNOWN), all from unknown dates for unknown indications and unknown if ongoing. The patient previously received the first dose of BNT162b2 (PFIZER-BIONTECH COVID-19 mRNA VACCINE; Lot Number: EP7534) via an unspecified route of administration in the arm left on 23Mar2021 at 11:00 (at the age of 26-years-old) as a single dose for COVID-19 immunisation and experienced no side effects. The patient also took previously sulfamethoxazole/trimethoprim (BACTRIM) and experienced allergy. On 13Apr2021, since the shot, the patient had  diarrhea on and off, headaches nearly constantly and at 23:45, the night after she got her second shot, the patient vomited profusely for about fourteen hours straight. The patient was unable to keep down food or water until late wednesday afternoon (around 16:00). She was also experiencing what feels like possible vertigo and kept getting dizzy. The patient felt off balance and when she turn her head the room started to spin. The patient was experiencing these events at the time of report and some nausea. It was Saturday at the time of report, which was four days after her second shot. She missed two days of work because her symptoms had been so severe and she had been feeling so weak. She had no side effects from the first shot at all. Her arm also had a large, hot, red circle where she took her shot. On an unknown date the patient underwent body mass index test and the result was 34.6(unspecified units). The adverse events did not result in doctor or other healthcare professional office/clinic visit and emergency room/department or urgent care. Therapeutic measures were not taken as a result of the reported events. Since the vaccination, the patient had not been tested for COVID-19. The clinical outcome of the events vomiting, diarrhea on and off,  headache nearly constantly, felt like possible vertigo, dizzy, felt off balance, nausea, feeling so weak and  large, hot, red circle where took the shot was not recovered at the time of this report.    No follow-up attempts are needed. No further information is expected.