I suppose you could look on the bright side of this and that is it was only a shot. The prednisone pills have to be taken for a certain amount of time and then tapered and I believe the amount of the steroid is more over that time.
I've had cortisone shots in the hip because of bursitis but that was before I was put on metformin. Mine peaked in the mid-200's for a couple of days and then went down.
You're right about
the carbs. It would be best to cut them out while your blood sugar is that high.
I'm glad you found us, too!