Unsteady and dizzy; Unsteady and dizzy; a lot pain everywhere from top to bottom; Weight loss; Has already fallen down three times. Gets imbalanced all of a sudden.; she couldn't swallow; she couldn't sleep at all; sick; Has already fallen down three times. Gets imbalanced all of a sudden.; This is a spontaneous report received from a contactable reporter(s) (Consumer or other non HCP). The reporter is the patient.  A 73-year-old female patient received BNT162b2 (BNT162B2), on 13May2022 at 08:30 as dose 3 (booster), single (Lot number: FM9992) at the age of 73 years, in left arm for covid-19 immunisation. The patient had no relevant medical history. There were no concomitant medications. Vaccination history included: j&j (Dose 1, LOT: 1805018, AE(s) following prior vaccinations: None), administration date: 12May2021, when the patient was 72-year-old, for Covid-19 Immunization, reaction(s): "No reaction"; j&j (Dose 2, LOT: 132281, AE(s) following prior vaccinations: None), administration date: 23Oct2021, when the patient was 72-year-old, for Covid-19 Immunization, reaction(s): "No reaction".  The following information was reported: BALANCE DISORDER (non-serious), FALL (non-serious) all with onset May2022, outcome "not recovered" and all described as "Has already fallen down three times. Gets imbalanced all of a sudden."; WEIGHT DECREASED (non-serious) with onset May2022, outcome "recovering", described as "Weight loss"; INSOMNIA (non-serious) with onset May2022, outcome "unknown", described as "she couldn't sleep at all"; DYSPHAGIA (non-serious) with onset May2022, outcome "recovering", described as "she couldn't swallow"; ILLNESS (non-serious) with onset May2022, outcome "unknown", described as "sick"; PAIN (non-serious) with onset 19May2022, outcome "recovered" (20May2022), described as "a lot pain everywhere from top to bottom"; GAIT DISTURBANCE (non-serious), DIZZINESS (non-serious) all with onset 20May2022, outcome "not recovered" and all described as "Unsteady and dizzy". The events "a lot pain everywhere from top to bottom", "unsteady and dizzy", "weight loss", "has already fallen down three times. gets imbalanced all of a sudden.", "she couldn't swallow" and "she couldn't sleep at all" required emergency room visit. Relevant laboratory tests and procedures are available in the appropriate section. Therapeutic measures were taken as a result of weight decreased.  Additional Information: Vaccination facility type was reported as mobile vaccine bus. The family medical history of patient relevant to AE(s) was reported as no relevant family history. All come from pretty healthy people. Grandmother lived to be 107 years old. It was reported that the patient called in regards to the Covid-19 Booster. Wanted to report that she had the booster on 13May2022 and five days later she had unbelievable reactions. Like full blow Covid type of reaction. Still had not gone away. Doctors did all kinds of blood tests. The patient clarified that she had a lot of pain everywhere from top to bottom. She was very unsteady and dizzy. She had never been sick, not on any medication, or anything like that. The booster had really done a number on her. Did not know what to do. Doctors did testing. Emergency room did a lot of testing, but they could not seem to find anything wrong. She knew it was the booster. She lost a lot of weight during all this. Did not have a PCP. Has never needed on. Pain everywhere from top to bottom: Described pain as excruciating. Pain went away the next day, but then, she couldn't sleep at all. Unsteady and dizzy: After the pain stopped, she started with the dizziness. Has already fallen down three times. Gets imbalanced all of a sudden. Started coming on slowly. Weight loss: Was not able to eat for four days. she couldn't swallow. would put food in her mouth but couldn't swallow it. 4-5 days later when she weighed herself. she lost about 6-7 pounds. Gotten slightly better. Taking ensure. The patient did blood work at the hospital (emergency room). Her WBC count was towards to high side. From 0-11, hers was 9. Fighting going on in her body. The visited the emergency room for Pain, unsteady and dizzy, weight loss but was not admitted. Additional vaccines administered on same date of the Pfizer suspect were none. Prior Vaccinations (within 4 weeks) were none.