felt heavy and dizzy; chills; flu-like symptoms; heart palpitations/felt like her heart was beating through her chest; horrible headache/Headache; Achy/little soreness the second day; nausea; felt heavy and dizzy; This is a spontaneous report from a contactable Nurse (patient). A 75-year-old female patient received second dose of BNT162B2 (PFIZER-BIONTECH COVID-19 VACCINE; Solution for injection; Lot number: EN6198) via intramuscular route in left arm on 20Feb2021 at noon (at the age of 75-year-old) as dose 2, single for COVID-19 immunization. Medical history of the patient included thyroid disorder. Concomitant products included thyroid medication and 5mg of Zocor. Patient confirmed these medications were taken prior to the 2-week time period leading up to receiving the vaccine. She has taken the thyroid medication all of her life and has been taking Zocor for 10 years, patient took Tylenol prior to receiving the vaccine. Patient did not receive any Prior Vaccinations (within 4 weeks). Patient previously received first dose of BNT162B2 (PFIZER-BIONTECH COVID-19 VACCINE; Solution for injection; Lot number: EL9262 [reporter can't tell what the first letter is. It's a squiggly line but it could be an "E"]) via intramuscular route in left arm on 30Jan2021 (at the age of 75-year-old) as single dose for COVID-19 immunization and had no problems at all. Reporter and her husband received the first COVID-19 vaccine and had no problems at all. Her husband was much bigger than she was and has had no problems at all. Patient received the second vaccine on Saturday-20Feb2021 and felt fine on Saturday. Sunday [21Feb2021], patient experienced all the flu-like symptoms. Patient had some nausea, a headache, she was achy. She felt a little better and had been taking Tylenol for a few days. This is her 6th day after receiving her second vaccine, and last night on 24Feb2021, she got the chills and a horrible headache all night. She didn't get out of bed for 10 hours. She was like heavy and a little dizzy on 24Feb2021. Patient clarified that she felt fine the day of 20Feb2021, however that night, her heart felt like it was beating through her chest [onset date: 21Feb2021]. If she would have read the information she was given, she would have probably gotten scared because it said a severe allergic reaction included heart palpitations. Her heart was in was in the 90's somewhere. Her heart rate was usually in the 70's. She has her apple watch back on and her heart rate is in the 70's. Last night, her heart rate was 85 and she could feel it pounding in her chest. It's a strange feeling. Today, she wasn't going to get out of bed and her husband told her maybe she should call her doctor considering the fact she got so much worse yesterday. The patient wants to know how many days does it usually take for symptoms to go away? She is so much smaller than her husband, so much more delicate and fragile, she doesn't understand just like with animals, why big ones get the same dose as little ones? Patient asked is there any advice on what she can take and shouldn't take? She took one Tylenol today, but she likes Aleve better. Somebody said to not take Aleve so she hasn't taken any. Patient asked is it okay to take Aleve since she was 5 days out? Also, can she take Allegra? Patient wants to know if she should get concerned about these symptoms and if she needs to go to the doctor? Is there anything better that she can take? Patient had blood test at Quest and couldn't get into the site, so she called and told them she just wanted to get her results. She clarifies she paid for the test and wanted to see the results. Patient took the Tylenol this morning, her head has improved, but since she has taken the Tylenol, the nauseousness was coming back. She has been drinking more Coca-Cola than she has ever in her life, it seems to help. Patient mentioned she had no soreness with the first COVID-19 vaccine. With the second vaccine, she had a little soreness the second day, but she took some Tylenol and the soreness felt better. The patient was told that you have to dilute the vaccine when it arrives. Reporter mentioned maybe she got a stronger dose than her husband, it can't be absolutely perfect every single time. Outcome of the events were unknown.  No follow-up attempts are possible. No further information is expected.