There is a achy pain under his armpit and he thinks it is linked to that, in his left armpit lymph node; There is a achy pain under his armpit and he thinks it is linked to that, in his left armpit lymph node; Got the Covid biontech booster third dose; he had a pretty sore left arm/The arm and shoulder is still sore; shoulder is still sore; The soreness is concentrated around the site of injection; left inner pectoral area is where the achy soreness is; This is a spontaneous report received from a contactable reporter(s) (Consumer or other non HCP). The reporter is the patient.  A 37 year-old male patient received bnt162b2 (BNT162B2), administered in arm left, administration date 10Dec2021 09:45 (Batch/Lot number: unknown) at the age of 37 years as dose 3 (booster), single for covid-19 immunisation. The patient had no relevant medical history. Concomitant medication(s) included: FLU, administration date 2021. Vaccination history included: Bnt162b2 (Second dose , Lot: unknown, Expiration: unknown, All three doses were administered in left arm), administration date: 05May2021, when the patient was 36 years old, for COVID-19 Immunization, reaction(s): "no soreness or anything with second dose"; Bnt162b2 (First dose , Lot: unknown, Expiration: unknown, All three doses were administered in left arm), administration date: Apr2021, when the patient was 36 years old, for COVID-19 Immunization, reaction(s): "little soreness of the arm with first dose". The following information was reported: IMMUNISATION (non-serious) with onset 10Dec2021 09:45, outcome "unknown", described as "Got the Covid biontech booster third dose"; PAIN IN EXTREMITY (non-serious) with onset 10Dec2021, outcome "not recovered", described as "he had a pretty sore left arm/The arm and shoulder is still sore"; ARTHRALGIA (non-serious) with onset 10Dec2021, outcome "recovering", described as "shoulder is still sore"; VACCINATION SITE PAIN (non-serious) with onset 10Dec2021, outcome "unknown", described as "The soreness is concentrated around the site of injection"; AXILLARY PAIN (non-serious), LYMPH NODE PAIN (non-serious) all with onset 12Dec2021, outcome "not recovered" and all described as "There is a achy pain under his armpit and he thinks it is linked to that, in his left armpit lymph node"; PAIN (non-serious) with onset 10Dec2021, outcome "unknown", described as "left inner pectoral area is where the achy soreness is".  Additional information: Consumer stated, "I received my third dose booster shot on Friday in the morning and I didnt experience any real side effects with the first two I think I just had a little bit of a sore arm on the first dose but thats why my arm is a lot more sore and just wanted to bring it up because I have soreness kind off little bit of an achy feeling in my armpit in my left arm where I got the shot in the like lymph node may be and the arm is still sore since then. It just seems like the pain have moved a little bit." There is a achy pain under his armpit and he thinks it is linked to that, in his left armpit lymph node. He thinks that is pretty much it and wanted to have this documented. Clarifies on Friday afternoon around the shoulder where the vaccination was administered was very sore and now it is diminished a little. Clarifies the achy soreness under left armpit started yesterday morning. He did not experience any of this with first two doses. He did have flu shot vaccine right around 4 or 5 weeks ago, he does not know the name or lot number of flu shot.   The lot number for bnt162b2 was not provided and will be requested during follow up.