Hi Audrey Ann,
Organicchick nailed it! Re-exposure to the pox in adulthood can very well cause shingles. I had them in 2004. It was one of the worst experiences of my life. If you notice any kind of blister on your body, get to your doctor ASAP. I can't stress that enough. You'll need an antiviral to combat it. It won't cure you, but the shingles will be less severe the quicker you get the antiviral in you.
Look for blisters that occur on only one side of your body. I'd check more than once a day for the next week or so, just to be sure.
Shingles will attack an immune system that is suppressed. So if you're on any immune suppressants, or chemo meds, you're at a higher risk. You are on pred and metho, so that puts you in the high risk category.
I REALLY hope you are free and clear. Fingers crossed!
Ginny