I wouldn't worry about a footprint in the immediate term. Footprints are mainly desgined to protect the tent floor from abrasion on rocky or otherwise abrasive surfaces, but that shouldn't be a big issue for a short trip. If the area is rocky, you might consider bringing along a small tarp to use as a groundcloth.

Depending on what kind of cooking you plan to do ("gourmet" vs. freezer bag or no-cooking), you might be able to get along with an aluminum or titanium cup and a spork instead of mess kit. Again, a thrift store would be a good place to scout out.

For layering, depending on when you're going I'd look at some sort of lightweight baselayer for campsite/sleeping. It's been fairly chilly here in the evenings of late (a few hours away from GSMNP, but relatively close!). Beyond that, I've been comfortable in short sleeves and long pants, although of course YMMV.

Have fun, and don't forget to post a trip report when you get back!