If your Wyeast activator pack is partially or fully inflated, this is not necessarily an indicator of bad yeast or mishandling during shipping. Some Wyeast activator packs, epseically 1056 American Ale, have a tendency to inflate during shipping. The inflation is due to residual co2 left over from propagation being released from solution during shipping and not usually from being activated. Most likely the yeast is still viable and should be alright to use. If the nutrient pack is still intact inside you should be able to activate it as usual and the pack should inflate the rest of the way.
A trick to activating slightly swollen packs is to turn it upside down so the nutrient pack is in the narrowest part and open the gussets on the bottom. Then squeeze the package with both hand in the middle forcing the co2 into the expanded area and then move your fingers downward feeling for the nutrient pack. Once you have isolated the pack in one of the corners you should be able to place it in the palm of one hand and smack it with the other.
If you were planning on making a yeast starter that will also work as a viability check for the yeast and will improve the overall health. If you are unable to feel the nutrient pack, the pack fails to inflate, or you are not making a starter let us know and we will be happy to send you a replacement.