Ok, so everything has gone well with restoring my world, and I set back to work on my 15x15 shaft.
I've gotten a couple of more blocks down, and have bumped into quite a few caverns opening up along the sides on my way down. I haven't really explored them all that much yet, only mining a bit of coal and occasionally some iron when it is visible. As of right now however, I have found a rather large one right smack dab in the middle of my shaft. While that does make things a little easier on me for the next couple of blocks down, there is a small problem. There is a spring in the cavern (see photo below).
If my observations are correct, the spring should very easily be plugged, and not interfere with the rest of my mining activities for the time being, but that isn't the only issue unfortunately.
On top of all of this, in the north east section of my shaft I keep hearing zombies and skeletons shooting their bows. I haven't actually seen any of them, nor taken any damage just yet. I am going to dig down a block or two before expanding out a bit, just to see if maybe I'm like 3 blocks away from a mob spawn or a dungeon. But not tonight... it is after 0200, and not gunna lie the zombie noises are starting to creep me out.
On a lighter note. While mining, specifically at night (yes... with the creepy zombie moans still) every now and then a chicken will float down, flapping its wings furiously. I had quite a few of those little buggers flapping around. It was quite the comic relief considering the circumstance. lol