Here's my recipe for the test "pumpkin spice" I sent you:

Brew #38 test of 1 gallon of pumpkin spice was prepared with 3.5 pounds costco honey, 1oz raisins, 1/4 tsp nutmeg, 1 small cinnamon stick, 3 tsp allspice, and 1 pound of Libby’s 100 percent pumpkin all natural with no preservatives from a can, with 1 tsp bread yeast.

It was a first try, and I was surprised how well it turned out. The bubbles may be secondary fermentation. When the mead is transferred from one contain to another, it can restart the fermentation process a little. You can't really taste the pumpkin much, but you can definitely taste the allspice!