I've been playing for about a year and when I started I bought myself a $50 pair of Nikes. Now I want to upgrade to a shoe that is very comfortable and also stable, but especially comfortable. After I walk 18 my feet are killing me cause my shoes feel like I'm walking on rocks. Which shoe would you all suggest?

Much of footwear comfort is about fit.
Footjoy's Classic and Classic Tour line comes in the largest selection of widths, so chances of getting a good fit with one of those models is very good. Also, these two models are the only golf shoes made with Goodyear welt construction (oustole stitched to the leather upper), which helps the shoe maintain its shape over a long period of time.
Unfortunately, Footjoy recently discontinued these two models and is closing down the only USA golf shoe factory. But, for the time being there is a good selection of these two models at internet retailers.
I recommend finding your correct size and width, then ordering a couple of pair. If you use shoe trees these will last you many years.
Other popular brands like Addidas, Nike, Ecoo, and most of Footjoy's line, are basically tennis shoe construction (outsole cemented on to the upper with adhesive) which loses its shape fast and not on par with the FJ Classic or Classic Tour models.

here is one retailer with a good selection of FJ Classics and Classic Tour's

www.golfshoesonly.com