>>12835420>>12836647>>12836874loling so hard at this samefriend who thinks that because i didnt use technical language like antigen presentation or primary/secondary response that my explanation is any less scientifically accurate.
what i've described through analogy is completely correct. let me use technical language just so i seem smart to you, though.
OP, the spike protein (made by the mRNA -- the mRNA is likely not causing any physiological in and of itself) is "harmless" compared with covid. the COVID-19 virus is this super complex virus which will hijack your body's systems in a way that leads to really severe symptoms. if your immune system didn't exist, the spike protein would just float around in your muscle cells and likely not do much of anything.
however, the spike protein IS immunogenic; that means it looks "weird" enough that the immune system is able to produce antibodies against it. or, to be technical, negative selection of your lymphocytes has led to a t-cell/b-cell repertoire that is highly reactive to non-self, and since the spike protein is highly non-self, there exists a b-cell/t-cell receptor that will bind to this antigen and direct clonal expansion, leading to the primary immune response.
after this activation, certain lymphocytes will differentiate into memory b-cells and t-cells, which persist in the body and lead to rapid activation of the immune system if they ever see this antigen pop up again.
so, OP, what's going on is that your body is correctly identifying the spike protein as an antigen from COVID -- just like if the spike protein was actually on the viral machinery itself. because this antigen is immunogenic, it's causing a primary immune response. those aren't really "side effects" -- they're just your immune system working (cont)