got some kind of under my arm swelling under my arm, where I had shot in; His under arm is swollen; I have went to get my second dose vaccine just today, the Pfizer but the first one, I took was Johnson and Johnson; booster; This is a spontaneous report received from a contactable reporter (Consumer or other non HCP). The reporter is the patient.  A 49-year-old male patient received bnt162b2 (BNT162B2), intramuscular, administered in arm right, administration date 24Dec2021 (Lot number: FL3198) at the age of 49 years as dose 2 (booster), single for COVID-19 immunization. The patient's relevant medical history was not reported. There were no concomitant medications. Vaccination history included: Johnson and Johnson vaccine (DOSE 1), administration date: 10Apr2021, when the patient was 49 years old, for COVID-19 immunization. The following information was reported: INTERCHANGE OF VACCINE PRODUCTS (non-serious) with onset 24Dec2021, outcome "unknown", described as "I have went to get my second dose vaccine just today, the Pfizer but the first one, I took was Johnson and Johnson"; IMMUNISATION (non-serious) with onset 24Dec2021, outcome "unknown", described as "booster"; VACCINATION SITE SWELLING (non-serious) with onset 25Dec2021, outcome "not recovered", described as "got some kind of under my arm swelling under my arm, where I had shot in"; LYMPHADENOPATHY (non-serious) with onset 25Dec2021, outcome "not recovered", described as "His under arm is swollen". Additional information: the consumer and reporter both were on the call (as reported). The consumer stated, "I have went to get my second dose vaccine just today, the Pfizer but the first one, I took was Johnson and Johnson and I want to make sure it's ok to me because and I got some kind of under my arm swelling under my arm, where I had shot in." The consumer stated, "This was a second follow up vaccine, it was the booster second." The consumer stated, "The next day, the next morning I got up the next morning, I started felling swelling up under my arm." Regarding the lot number, the consumer stated, "I don't have the number to the booster shot, that's all at the (Pharmacy Name)." Regarding the expiration date, NDC number, and UPC number, the consumer stated, "I don't have any of that." The reporter then stated, "Do you understand he has got the Pfizer in April or May or something, I mean he wouldn't got the J &J in April or May or something and he is missing, it would have Pfizer are you understanding me, he wouldn't got the J and J Friday, he woke up this morning and his arm was swell, swell, ok we got the lot number right here, the Lot number is FL3198."  The reporter then stated that the first dose was Johnson and Johnson on 10Apr2021, and the second dose of vaccine was Pfizer on 24Dec2021.  Regarding the anatomical site of the vaccine administration, the reporter stated, "The Johnson and Johnson at (facility name) and the Pfizer was at (pharmacy name) '14-09', the right arm in the muscle." Regarding other medical conditions, the reporter stated, "his under arm is swollen." Regarding other medications, the reporter stated the patient was not taking any medication. When the reporter was asked if the consumer was still experiencing the issue, the reporter stated, "Yes still swollen, got bigger." The reporter stated that the outcome of event was "persisting." As for if the consumer received treatment, the reporter stated, "no he have not done nothing so he just woke up and swollen." When asking for any further assistance, the reporter asked what they could do, regards to the doctor or emergency room; wanted to know that during this time period, what they could do.