swelling behind the knees and swelling of the veins; it had to do with blood clot warnings / it was some kind of clotting because of the position of the areas of swelling.; she got like three balls on the right arm; pain in her left arm from the armpit to the elbow, it was a line of pain going down the arm; the lymph nodes in left armpit got swollen; swelling behind the knees and swelling of the veins/ she had swelling under her armpit and swelling on her right arm below her elbow; This is a spontaneous report received from a contactable consumer. A 48-years-old female patient received bnt162b2 (BNT162B2), dose 1 via an unspecified route of administration, administered in Arm Left on 12Apr2021 10:30 (Batch/Lot Number: ER8729) as SINGLE DOSE for covid-19 immunisation.  Medical history included covid-19 from Nov2020 to an unknown date. The patient's concomitant medications were not reported.  The patient experienced it had to do with blood clot warnings / it was some kind of clotting because of the position of the areas of swelling on 15Apr2021, swelling behind the knees and swelling of the veins, swelling behind the knees and swelling of the veins/ she had swelling under her armpit and swelling on her right arm below her elbow on 12Apr2021, the lymph nodes in left armpit got swollen on 13Apr2021, pain in her left arm from the armpit to the elbow, it was a line of pain going down the arm on 14Apr2021, she got like three balls on the right arm on 15Apr2021.  The patient underwent lab tests and procedures which included ultrasound scan: unknown results.She was calling because she got her shot on 12Apr2021 and then she ended up having swelling behind her knee, then she had swelling under her armpit and swelling on her right arm below her elbow. She stated that they weren't lymph nodes, and she went to the ER (EmergencyRoom) had to check and see if they were blood clots. She stated that it turns out that her veins were swollen underneath her arm. She said that was what happened after the shot and that was her first shot. She states so that's her report on what happened.  She stated she got the shot in the morning so her symptoms at 6 or 7 pm that evening. She stated she went to the doctor first and then went to the hospital. She went to the doctor on the 16Apr2021 and the hospital on 16Apr2021. She stated that the swelling behind her knee went away on 20Apr2021.Tuesday, 13Apr2021 the lymph nodes in left armpit got swollen. On Wednesday, 14Apr2021, there was a pain in her left arm from the armpit to the elbow, it was a line of pain going down the arm. On Thursday, 15Apr2021 she states she got like three balls on the right arm, on her elbow on the right side. She went to the doctor on Friday 16Apr2021 she went to the ER (emergency room) because they couldn't figure out if it was some kind of clotting because of the position of the areas of swelling. She got an ultrasounds for them to check her blood flow. She stated that the pain in her left arm was going down but didn't resolve until the 22Apr2021. For the little balls on her arm, the MD  (Medicne Doctor) gave her a medication for the swelling of her veins but she forgot the name and she doesn't have the paper with her. She states the balls of fluid went away between the 20Apr2021 and 22Apr2021. Everything starting going away that week.She states it had to do with blood clot warnings, and swelling under her skin had to do with the veins. Outcome of with blood clot warnings was unknown, like three balls on the right arm and pain in her left arm from the armpit to the elbow was recovered, remaining events was recovering.Therapeutic measures were taken as a result of swelling behind the knees and swelling of the veins/ she had swelling under her armpit and swelling on her right arm below her elbow, she got like three balls on the right arm.