I made my first pumpkin ale a few weeks ago, I'l taste it on Thanksgiving.
I'd guess the active fermentation and higher gravity are from the extra sugar in the pie mix. I bet it tastes good. Maybe a little stronger and drier than some recipes, since it probably has more sugar to ferment. That isn't a bad thing, probably will be great. Hopefully you can reproduce it, if you like how it comes out, just keep track of what you did so you know.