fever; chills; bad headache; nausea; her stomach is really bothering her and hurts a lot; loss of appetite/no appetite; can't eat; pain with her stomach; She wanted to know so she can stop wondering if she is dying; This is a spontaneous report received from a contactable reporter(s) (Consumer or other non HCP) from medical information team. The reporter is the patient.  A female patient received bnt162b2 (BNT162B2) (Batch/Lot number: unknown) as dose 4 (booster), single for covid-19 immunisation. The patient's relevant medical history and concomitant medications were not reported. Vaccination history included: Covid-19 vaccine (DOSE 1, SINGLE, Verbatim: she never had a reaction to any of the prior vaccine doses.), for COVID-19 Immunization; Covid-19 vaccine (DOSE 2, SINGLE, Verbatim: she never had a reaction to any of the prior vaccine doses.), for Covid-19 Immunization; Covid-19 vaccine (DOSE 3, (BOOSTER) SINGLE, Verbatim: she never had a reaction to any of the prior vaccine doses), for Covid-19 Immunization. The following information was reported: PYREXIA (non-serious), outcome "recovered", described as "fever"; CHILLS (non-serious), outcome "unknown", described as "chills"; HEADACHE (non-serious), outcome "unknown", described as "bad headache"; NAUSEA (non-serious), outcome "unknown", described as "nausea"; ABDOMINAL DISCOMFORT (non-serious), outcome "unknown", described as "her stomach is really bothering her and hurts a lot"; DECREASED APPETITE (non-serious), outcome "unknown", described as "loss of appetite/no appetite"; EATING DISORDER (non-serious), outcome "unknown", described as "can't eat"; ABDOMINAL PAIN UPPER (non-serious), outcome "unknown", described as "pain with her stomach"; FEELING ABNORMAL (non-serious), outcome "unknown", described as "She wanted to know so she can stop wondering if she is dying".  Additional information: She was reporting that she never had a reaction to any of the prior vaccine doses but had a pretty severe reaction this time (after her second booster dose). She had fever, chills, a bad headache, nausea, her stomach is really bothering her and hurts a lot, and loss of appetite. She wanted to know so she can stop wondering if she is dying. This is her 4th dose and she had no reaction until 30 hours after. She took the vaccine at 10:00 on Sunday and symptoms started at 4:00 the next day and were really bad. She woke up tired and her stomach started hurting, her stomach was really hurting and she had no appetite. She knew some of these symptoms were possible with the vaccine but the pain in her stomach and not being able to eat after 3 days was what she was concerned about and she thought it would be going away. She is worried because it is not going away. She stated she experienced very little the previous times [that she had the vaccine] and with those it went away in short time. She stated she was going to call her doctor. She does not have fever anymore but really in pain with her stomach. She is not sure if these events are normal, does not know if this is an abnormal response to the product and wanted to know if normal or not so she can stop wondering if she is dying. She looked it up, but does not see this, they don't say it lasts this long, they say you can have nausea.  The lot number for bnt162b2 was not provided and will be requested during follow up.