a sharp pain was coming from the side of my back and shooting to my left breast/ a muscle on the side going down of my back/ sharp pain when I make a turn or reach that goes to my breast; when she moves that she has a pain that goes through the lymph nodes or muscles behind her left breast; when she moves that she has a pain that goes through the lymph nodes or muscles behind her left breast; pain was either from something in her left shoulder, or the left side of her back, or a muscle; feeling a little down and out; she can't sleep in the heat at night; This is a spontaneous report from a contactable consumer (patient). A 73-year-old female patient received the first dose of BNT162B2 (PFIZER-BIONTECH COVID-19 VACCINE, solution for injection, Lot number: EL8982 ), via an unspecified route of administration at left upper arm on 23Jan2021 16:00 at single dose for COVID-19 immunization. There were on patient medical history and concomitant medications. No additional vaccines administered on same date of the Pfizer suspect. No prior vaccinations (within 4 weeks).The patient said she did good on Saturday, 23Jan2021, saying her left arm didn't get sore. She said she did good on Sunday, 24Jan2021. She stated "I didn't get sore, but it just seemed like maybe a few days ago it seemed like a sharp pain was coming from the side of my back and shooting to my left breast (on 25Jan2021). It only does it when I am lying down and not when I am sitting down. I drank plenty of water and continue to drink plenty of water. Today, I am feeling a little down and out because of my breast (25Jan2021). My breast itself is not sore at all. It seems like maybe a muscle on the side going down of my back. There is a sharp pain when I make a turn or reach that goes to my breast. Well, if you have arthritis it could be that." She said it seemed when she moves or turns, she has a sharp pain in her left breast. The patient asked if the sharp pain she was experiencing in her left breast area were possibly her lymph nodes. She clarified her left breast was not sore, but the area behind her left breast has a pain go through it. She said it was just when she moves that she has a pain that goes through the lymph nodes or muscles behind her left breast. She said she normally doesn't sleep on her left side, but if she sleeps on her left side, the pain behind her left breast was better. She said she does not have big breasts and was not wearing a bra when she had the pain in her left breast area. She said she was wondering if the pain she has is from her lymph nodes or muscles in her back. She said the pain was either from something in her left shoulder, or the left side of her back, or a muscle. As treatment, patient reported that she has been holding her left breast area when she moves. She said holding the left breast area helps lessen the pain, but the pain was still there. She said she has been trying to troubleshoot her pain. She said she drinks coffee every day and thought maybe she was drinking too much caffeine. She said she can't sleep in the heat at night, so she turns the heat off in her house at midnight, but her house was still warm (70 degrees) when she wakes up in the morning. She said she thought that maybe the cold weather got into her back and left shoulder. She said she checked her left breast for lumps and didn't find any lumps. She said the only thing left for her to do was to contact her gynecologist and go have a mammogram. She doesn't take any medicine. She said she does take something for sleep as needed, but she would have to be going without sleep for a long time before she would take that medicine. She reported she is otherwise a healthy person. She said people talk about hormones changes after when a person used to have a period, and she sometimes doesn't know if her pain would be because of that. She said she may have irritation in her breasts from wearing a bra that may be too tight, but the pain she was experiencing now was different from that pain. The events did not require a visit to Emergency Room or Physician Office. The outcome of the events she can't sleep in the heat at night and feeling a little down and out was unknown; and not recovered outcome for the other events.