Hi there,
There are a few possibilities here. One cause is a
hematoma (blood underneath the skin) that may have traveled down from the injection site to your elbow joint. This is probably less likely, as you'd notice bruising down your entire forearm.
Another possibility is an infection that travels down the area of injection to the joint space. This would be accompanied by
redness, heat, and worsening pain, as well as fevers and chills. Finally, the last thing that is possible is an
allergic reaction, although this is also unlikely as
cortisone is a naturally occurring hormone in the body.
A third possibility is swelling causing nerve compression and pain.
For my clinic patients, I usually recommend warm compresses which you have been doing. I recommend a 15 minute on/15 minute off interval at the minimum, but you can increase the interval on time.
Ibuprofen will be helpful here, and as long as you don't have a history of stomach ulcers or kidney problems, you can take 800mg every 8 hours as needed. You can also try some
benadryl, which may help as well with swelling.
I'd try doing those two things. If your pain doesn't get better or your symptoms worsen, then I'd follow up with the doctor who gave you the injection. if you start having fevers, chills, nausea, or
vomiting, then go to seek medical attention sooner. I hope this is helpful.