I've been having pain in my left armpit for a few hours. Feel it worst when I move my arm. It just started all of a sudden. I'm not sick. If your AI disease is flaring, can it swell your lymph node in your armpit? Is your lymph node in your armpit or below? I'm leaving in an hour for surgery, not sure what's wrong here. I've never had my lymph node in my arm to swell. And I don't even know for sure if that is what is wrong. But I sure didn't strain/hurt myself, I had to quit taking my anti-inflammatory last week though for the surgery. I've sit up all night waiting to go to the hospital. I am feeling run down.