Don't Be Worried if Your br Arm Hurts After a Flu Shot After getting a vaccine for the flu, br your limb will usually feel pretty sore. Medical experts say br that is a good sign. Forward medical lead Nate Favini, via HuffPost It it also an indicator that antibodies are br being created by your immune system. This is in preparation if you br get influenza at some point. If you want to feel less pain, there br are a couple things you can do. Huntington Hospital CMO br Michael Grosso recommends br moving your arm around right away. Grosso says this will circulate blood and br oxygen to the muscles in your limb. Putting a cooled compress on the br area where you received the br shot will also reduce pain. Grosso adds that medication, such as ibuprofen, br can be taken as well. You may feel discomfort, but don't let that keep you from getting the vaccine.