I never felt this bad in my entire life; I missed 3 weeks of work/not being able to function; My left arm was tensed up.; I have depression from not being able to function; pain everywhere; Whole left side of body from middle of chest down to arm felt pain and tense; Arm felt pain; muscle pain/muscle aches; I'm having breathing problems/I can't catch my breath; difficulty walking/I can't walk from one room to the next; This spontaneous case was reported by a consumer and describes the occurrence of DYSPNOEA (I'm having breathing problems/I can't catch my breath), FEELING ABNORMAL (I never felt this bad in my entire life), LOSS OF PERSONAL INDEPENDENCE IN DAILY ACTIVITIES (I missed 3 weeks of work/not being able to function), LIMB DISCOMFORT (My left arm was tensed up.) and DEPRESSION (I have depression from not being able to function) in a 49-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch nos. 053E21A, 012A21A and 001B21A) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.     No Medical History information was reported.  Concomitant products included LEVOTHYROXINE SODIUM (SYNTHROID) for an unknown indication.   On 25-Feb-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On 25-Mar-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. On 17-Sep-2021, received third dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. In September 2021, the patient experienced DYSPNOEA (I'm having breathing problems/I can't catch my breath), GAIT DISTURBANCE (difficulty walking/I can't walk from one room to the next) and MYALGIA (muscle pain/muscle aches). On an unknown date, the patient experienced FEELING ABNORMAL (I never felt this bad in my entire life), LOSS OF PERSONAL INDEPENDENCE IN DAILY ACTIVITIES (I missed 3 weeks of work/not being able to function), LIMB DISCOMFORT (My left arm was tensed up.), DEPRESSION (I have depression from not being able to function), PAIN (pain everywhere), CHEST PAIN (Whole left side of body from middle of chest down to arm felt pain and tense) and PAIN IN EXTREMITY (Arm felt pain). The patient was treated with PREDNISONE for Adverse event, at an unspecified dose and frequency; ALBUTEROL [SALBUTAMOL] for Adverse event, at an unspecified dose and frequency; DOXYCYCLINE for Adverse event, at an unspecified dose and frequency; PARACETAMOL (TYLENOL) for Adverse event, at an unspecified dose and frequency; LEVOFLOXACIN (LEVAQUIN) for Adverse event, at an unspecified dose and frequency and FLUTICASONE FUROATE, UMECLIDINIUM BROMIDE, VILANTEROL TRIFENATATE (TRELEGY) for Adverse event, at an unspecified dose and frequency. At the time of the report, DYSPNOEA (I'm having breathing problems/I can't catch my breath), GAIT DISTURBANCE (difficulty walking/I can't walk from one room to the next) and MYALGIA (muscle pain/muscle aches) had not resolved and FEELING ABNORMAL (I never felt this bad in my entire life), LOSS OF PERSONAL INDEPENDENCE IN DAILY ACTIVITIES (I missed 3 weeks of work/not being able to function), LIMB DISCOMFORT (My left arm was tensed up.), DEPRESSION (I have depression from not being able to function), PAIN (pain everywhere), CHEST PAIN (Whole left side of body from middle of chest down to arm felt pain and tense) and PAIN IN EXTREMITY (Arm felt pain) outcome was unknown.