The muscle would not relax, it was dense as hell; it was horrible and that wasn't painful, as much it was lack of function, it's like my arm doesn't want to lift itself up; lot of muscle in my arm where at the injection site, may be half outside, actually I didn't measure it; Weakness; Soreness in whole body and arm; Soreness in whole body and arm; I took my arm and lured myself to do things which were extremely difficult. This is a spontaneous report received from a contactable reporter(s) (Consumer or other non HCP). The reporter is the patient. An adult male patient received bnt162b2 (BNT162B2), intramuscular, administered in arm left, administration date 23May2021 (Lot number: ER8734) as dose 2, single for covid-19 immunisation. The patient's relevant medical history and concomitant medications were not reported. Vaccination history included: Bnt162b2 (Dose:1, LOT#ER8735), administration date: 27Apr2021, for Covid-19 immunization. The following information was reported: MUSCLE TIGHTNESS (non-serious) with onset 2021, outcome "unknown", described as "The muscle would not relax, it was dense as hell"; INJECTED LIMB MOBILITY DECREASED (non-serious) with onset 2021, outcome "unknown", described as "it was horrible and that wasn't painful, as much it was lack of function, it's like my arm doesn't want to lift itself up"; VACCINATION SITE MASS (non-serious) with onset 2021, outcome "recovered" (2021), described as "lot of muscle in my arm where at the injection site, may be half outside, actually I didn't measure it"; ASTHENIA (non-serious) with onset 2021, outcome "unknown", described as "Weakness"; PAIN IN EXTREMITY (non-serious), PAIN (non-serious) all with onset 2021, outcome "recovered" (2021) and all described as "Soreness in whole body and arm"; LOSS OF PERSONAL INDEPENDENCE IN DAILY ACTIVITIES (non-serious) with onset 2021, outcome "unknown", described as "I took my arm and lured myself to do things which were extremely difficult.". Therapeutic measures were not taken as a result of vaccination site mass, pain in extremity, pain.  Additional information: It was not related to a study or programme. He had about a muscle in left arm that was not loosen and if you know anything about muscle when they are not loosen not only it is Uncomfortable but not necessarily painful. it's just does not, so that means his 30 plus pounds goes from the light weight to the heavy because the whole of his left arm was not want to work for the first time around. It was COVID arm. When probed for the concern, consumer stated, He had a few questions. He had series of questions here some side effects which are not listed on official form for your (Pfizer) Vaccine and nobody told me about it, so the first question he have is that. He was not a Doctor there is something he know about the Pfizer vaccine that temporary hijacked the muscle cell to produce antibodies. Not antibodies but they produce something which body reacts to it. We use the energy in the muscle cells to produce things which your body says hey you don't like this, you get Covid, and you don't go to the Hospital and die. So patient asked, how muscle cells work. When you work out your muscle cell torn part eventually and broken down and then they become stronger, so does the vaccine hijack the muscle cells. Consumer was informed about the Role of Pfizer Drug Safety. Consumer was informed about Pfizer Medical Information Department. Consumer stated, This was related to the vaccine and this questions were related to Pfizer Covid-19 Vaccin. That would be good if your automated system to specify, it really would be. Please update and that would be nice, so one of the side effects not listed anywhere I think it is weakness and ball of muscle after I got both 1st vaccine and the 2nd vaccine (doses) in which is in two step process. That was about a lot of muscle in my arm where at the injection site, may be half outside, actually I didn't measure it.  The muscle would not relax, it was dense as hell. It wasn't painful. It's just it didn't work well. As the muscle would not relax for about 4-5 days period in my whole left arm because it was in my left arm. Things which were should not be heavy were heavy and that was not listed anywhere. The symptoms were soreness and there were whole symptoms for whole body and the arm. But there were not about lot of muscle which would not relax. Outside the injection site, the muscle would relax but it didn't want to work. Things that put in this way. I couldn't use my half hand because it didn't work well. Anywhere from 1-5 days after I got the vaccine, my left arm didn't want to work, it's like it doesn't want to work. What worst is that I am stubborn and I am not willing to accept, there is any stupid limitation because of the vaccine, so I took my arm and lured myself to do things which were extremely difficult. My arm didn't get sore because of the vaccine, my arm got sore because I pushed it and pushed it to do things which would normally do with no efforts. I have lots of back muscles and my shoulder muscle are strong. I am a large male. I am 6 feet 3 inches 250 pounds. I am strong as hell. So what's worst about is this not only my whole left arm is sore but weak. But the bigger issue is my muscle don't want to work. My arm wasn't numb, it wasn't that weak. But had I known about it that I would have taken 4-5 days off afterwards. Then would have vaccine on Thursday, then would have taken Friday off then Saturday Sunday off, would have taken Monday Tuesday off. Everyday things were difficult, my left arm didn't want to work. What worst is this my shoulder tried to compensate for it. Here is the problem my shoulder muscle would do things that my arm muscle would normally do. That time I hadn't listen to my body, I would trip my shoulder, so the bigger issue is no body told me about this. Nobody told me to take it easy for 4-5 days, don't try to push it, your arm is going to be (incomplete sentence). Nobody did that, so I just did when I normally did. First dose vaccine LOT#ER8735 First dose vaccination date: 27Apr2021 Second dose Vaccine LOT#ER8734 Second dose vaccination date: 23May2021 When probed for vaccine Expiration date, consumer stated, he don't have the vaccine that was given,he don't have the vials, he don't know when they expire. Vaccination Anatomical: Left arm When probed for vaccination Route of administration if intramuscularly, me to get back to normal. I did every things that I would normally do. While the weakness was occurring. Pushing my arm beyond that normally would do, so my shoulder had to compensate it. My back and shoulder muscle had to compensate for the arm muscle which was not functioning properly. Because of that I almost tripped my shoulder, I almost tripped my back. Any Prior vaccination (within 4 weeks) was not reported. Those (first and second Covid doses) were his first shots in probably 3 years.  No follow-up attempts are needed. No further information is expected.; Sender's Comments: Linked Report(s) : US-PFIZER INC-2021486958 same reporter/patient/product, different dose/event.