It sounds like it could be either betamethasone, or dexamethasone. I don't know too much about betamethasone, but dexamethasone is used very often in the veterinary world. They are both steroidal anti-inflammatory drugs. I believe that dexamethasone is more potent, but don't hold me to that.
I'm glad to hear that your first appointment went well. Hopefully the pain you have from the injections now will pay off & they will bring you some relief in a couple of days! Let us know how things go! Until then, feel better!