Also, it was approximately 3' tall when I planted it

I have some banana trees as well and it does take some time for the trees to establish themselves and start new growth. I had to move mine to southern side of our house to protect them from winter cold fronts, I don't know much about your area since I live the deepest southern part of Texas (very tropical, hot, humid), but those 90 degree temps are what banana trees like! Just give it some time- about another week or so. If nothing seems to happen after two weeks or it starts wilting, cut down the tree. And its ok if the tree dies, banana trees have a huge corm (mass where the roots come out), this is where new banana plants will start growing even after the mother tree dies.

It will probably just take a little time for it to adjust. I dug a few of mine up last fall and brought them in for the winter, just transplanted them outside last week, and they're not doing much yet. But last summer they grew to about 8' tall and produced a bunch of offshoots (I live in NJ.)