A long story short. The procedure did not go as planned. I've spent 2 of the past 4 days in the emergency room. The first time (Thursday evening) was because of severe pain and pressure I was still having after the injection.
The next day, a complication from the epidural injection appeared. The doctor evidently punctured a membrane, which left cerebrospinal fluid leaking at the injection site, causing an imablance in fluid around my brain. This caused debilitating, low-pressure headaches and nausea with any attmept to sit up, stand, or walk. After 36 hours in this condition, I was in the ER this morning to receive a blood patch. This process takes blood from my arm, which is then injected into the epidural area to "patch" the hole where the cerebrospinal fluid is leaking. The procedure went quickly, and the relief was almost immediate. I'm on bedrest for the day, and I still have some back pain, but the odds are in my favor now (95% success rate). Some tenderness at the epidural site, but headaches are gone!