Numbness in my hand/fingers; Blood results came back with an end note "unable to report due to significant platelet clumping"; White blood cell count: (02Dec2021) 3.2 L; Blood pressure was 156/100 mmHg/ Hypertension; Pain/soreness in left arm/ soreness extended to my entire left arm; Muscles in arm are jumping (twitching) and it's burning; Muscles in arm are jumping (twitching) and it's burning; Unable to sleep; Pain in the upper left side of my chest; Neck stiffness; This is a spontaneous report received from a contactable reporter (consumer) from medical information team. The reporter is the patient.  A 36-year-old female patient received BNT162B2 (PFIZER-BIONTECH COVID-19 VACCINE), administered in arm left, administration date 01Oct2021 (lot number: FF2587) at the age of 36-years as dose 2, single for COVID-19 immunisation. The patient had no relevant medical history. There were no concomitant medications. Vaccination history included: BNT162B2 (lot number: FC3184, administered in left arm as dose 1, single), administration date: 10Sep2021, when the patient was 36-years-old, for COVID-19 immunisation. The following information was reported: HYPERTENSION (medically significant) with onset 02Dec2021, outcome "unknown", described as "Blood pressure was 156/100 mmHg/ Hypertension"; PAIN IN EXTREMITY (non-serious) with onset 01Oct2021, outcome "not recovered", described as "Pain/soreness in left arm/ soreness extended to my entire left arm"; MUSCLE TWITCHING (non-serious) and MYALGIA (non-serious) all with onset 01Oct2021, outcome "not recovered" and all described as "Muscles in arm are jumping (twitching) and it's burning"; INSOMNIA (non-serious) with onset 2021, outcome "unknown", described as "Unable to sleep"; CHEST PAIN (non-serious) with onset 2021, outcome "unknown", described as "Pain in the upper left side of my chest"; MUSCULOSKELETAL STIFFNESS (non-serious) with onset 2021, outcome "unknown", described as "Neck stiffness"; PLATELET DISORDER (non-serious) with onset 02Dec2021, outcome "unknown", described as "Blood results came back with an end note "unable to report due to significant platelet clumping""; WHITE BLOOD CELL COUNT DECREASED (non-serious) with onset 02Dec2021, outcome "unknown", described as "White blood cell count: (02Dec2021) 3.2 L"; and HYPOAESTHESIA (non-serious), outcome "unknown", described as "Numbness in my hand/fingers". The events "pain/soreness in left arm/ soreness extended to my entire left arm", "muscles in arm are jumping (twitching) and it's burning", "unable to sleep", "pain in the upper left side of my chest" and "neck stiffness" were evaluated at the physician office visit. The patient underwent the following laboratory tests and procedures: blood pressure measurement: (02Dec2021) 156/100 mmHg; blood test: (02Dec2021) platelet clumping, notes: Unable to report due to significant platelet clumping; body mass index: (02Dec2021) 30.38; heart rate: (02Dec2021) 83 bpm; oxygen saturation: (02Dec2021) 97 %; respiratory rate: (02Dec2021) 18 bpm; and white blood cell count: (02Dec2021) 3.2 L. Therapeutic measures were taken as a result of pain in extremity, muscle twitching, myalgia, chest pain, and musculoskeletal stiffness. Clinical course: The patient received the second dose of the purple cap of Pfizer COVID-19 vaccine on 01Oct2021 and after which, she started having pain/soreness in her left arm. She could feel the muscles in her arm jumping (twitching) and burning. She thought it would go away with time, but it got worse, the soreness extended to her entire left arm and it was painful. She was unable to sleep due to intense pain. She also experienced pain in the upper left side of her chest and her neck stiffness became unbearable, so she visited a doctor on 02Dec2021 where she completed a CBC blood testing. Her blood pressure was 156/100 mmHg and mentioned that she never had hypertension before. Her blood results came back with an end note "unable to report due to significant platelet clumping"; she never had the issue before either. The doctor prescribed Naprosyn for pain but it was not helping. She then experienced numbness in her hand/fingers. Family history relevant to the adverse events, prior vaccinations within 4 weeks, and vaccines administered on the same date of the Pfizer suspect were reported as none.