right breast pain; Shoulder pain; can't move shoulder/ can't move her arm/ her shoulder is immobile; Shortness of breath; Anxiety; breast is hard; shoulder pain was going down her back to the trapezius/ all the way to the back; This is a spontaneous report from a contactable nurse, the patient. This 64-year-old female patient reported for herself that she received the second dose of BNT162b2 (PFIZER-BIONTECH COVID-19 mRNA VACCINE, Batch/lot number: ER8731) via an unspecified route in the left arm on 18Apr2021 at 12:15 (at the age of 64-years-old) as a single dose for COVID-19 immunization. Medical history included tick bite, blood pressure, nerve pain, gastroesophageal reflux disease (GERD), and sciatica. The patient had no family history. The patient had no other prior vaccinations (within 4 weeks) of the COVID vaccine. Ongoing concomitant medications included olmesartan for blood pressure, duloxetine for nerve pain, omeprazole for GERD, famotidine for GERD; all taken for years, meloxicam for sciatica taken for 2 months and ongoing and doxycycline from 16Apr2021 and ongoing for tick bite (reported that she kept forgetting to take it). The patient previously received the first dose of BNT162b2 (PFIZER-BIONTECH COVID-19 mRNA VACCINE, Lot Number: ER8727) on 28Mar2021 at 12:00 in the left arm as a single dose for COVID-19 immunization. That dose went in the deltoid and she had no issues. Then she received the second dose on 18Apr2021 at 12:15 in the left arm. She believes it was administered in the soft tissue behind the deltoid. She noticed the person who gave the injection went behind the muscle toward the back of the arm. The next day after the second dose, she felt fine. Then the second morning it felt as if her shoulder was dislocated; and her breast is hard and painful; and she can't breath. She called her doctor who said that was not a common side effect but she stated she knows it is a side effect. The doctor recommended she go to the ER but patient didn't want to go. She stated that she doesn't know if missing the muscle is going to let the medication absorb or if it has penetrated the soft tissue. The clinical course of events was further described as follows: On 20Apr2021 at 08:00, the second morning, she woke up and felt severe pain in her right breast and shoulder all the way to back; adds she can't move her arm and her breast is so painful she can't touch it and her shoulder is immobile. She is also having very bad shortness of breath, adds she thought that may be from anxiety; so later in the day she took a alprazolam (XANAX). She added that she put up with the pain all morning and thought maybe she was working herself up so she took one half of a Xanax to calm down, to see if it was just anxiety but the shortness of breath and pain were still there. She reported she was continuing to feel all of these effects at the same level. She doesn't want to go to the ER because of the expense. The shoulder pain was going down her back to the trapezius. She clarified that she can move her shoulder and her arm, but the pain was so breathtaking that she doesn't move it and she has her arm in a sling. There were no relevant tests performed. The clinical outcome of the events right breast pain, breast is hard, shoulder pain, shoulder pain going down her back, shortness of breath, can't move shoulder/arm/ shoulder is immobile, and anxiety was not recovered. The patient mentioned that she doesn't know if not getting the shot in the deltoid caused her symptoms or not.; Sender's Comments: Based on chronological connection to the vaccine a causal relationship between reported events and BNT162b2 (PFIZER-BIONTECH COVID-19 mRNA VACCINE) cannot be completely excluded. The impact of this report on the benefit/risk profile of the Pfizer product is evaluated as part of Pfizer procedures for safety evaluation, including the review and analysis of aggregate data for adverse events. Any safety concern identified as part of this review, as well as any appropriate action in response, will be promptly notified to Regulatory Authorities, Ethics Committees and Investigators, as appropriate.