Why does my arm hurt after the flu shot?

when you get the injection, the muscles are not used to it and they tighten up around the area in which the needle went. Somewhat similar to working out, ish.

Your body is fighting off the foreign substance that was introduced into it. The pain is your nervous system’s way of letting your concious being know there is a problem, and where it is.

You had a big-ass needle in your arm!

@simone54 actually the needle wasn’t that large.

Local inflammation. Nothing to worry about. Put ice on it.

The technical term is a BIG booo-boooo. It is just reaction to the needle and the flu vaccine in your body. Ice packs and aspirin should help.

Hm… Mine didn’t hurt after I got mine… Weird. Probably some sort of sensitivity you have. or maybe they mixed up the shots and gave you a tetnus one. LOL. Take some pain medication, and you’ll be fine. If it stays for more than a week, I suggest you see someone about it. :)