Talk to Neuro Physician on Lump After Injection

About a year ago, I received a 3 mL diclofenac injection in the outer aspect of my left upper arm (around 4 inches above the elbow). Since then, I've had a persistent lump at the injection site. It's only tender when I press on it; otherwise it has never really bothered me.

About a week ago, I went to a clinic with a severe migraine and was prescribed an injection (I'm not sure what medication it was). Unfortunately, the nurse inserted the needle directly into the same lump. I didn't notice at first because my headache was so severe, but as soon as she started injecting the medication, I experienced intense pain. I immediately asked her to stop, and she did. I estimate that about 1 mL had already been injected.

Since then, I've been having a strange sensation in that area whenever I move my arm. It feels like a bite/pinch or as if something inside is being pulled or tugged with certain movements. There's also pain with movement. It's not severe, but it's persistent and wasn't present before this injection. At rest, I have little to no pain.

Please guide.

Thank you.