Anyway, my adventure reached a climax yesterday. (I used the term "a climax" because it's still just one of my adventurous endeavors.) One morning, I left my tower base (it has 5 stories) and ventured off to the east. I went through the eastward tunnel I dug, and after reaching it's mouth (a small shed in the overworld), I went out and closed the door. Behold, a large and unexplored plains! I kept walking to the east, bypassing wandering sheep, trees, ravines, and grass. Then I reached the sea and crossed it.
Upon crossing the sea, I entered a different biome full of tall trees and grass (and sheep, again). I kept walking forward, leaving behind some traces such as sand pillars and torches seldomly. When nightfall came, I switched to "peaceful mode" in order to continue travelling without having to fend off hordes of monsters.
(In the real world, I saved my game and took a break. This would later on cause something.)
When morning came, I continued walking and behold - a new sea complete with lily pads. I tried swimming to the other side but I realized how far I've already wandered off. So I swam back to the shore and walked back. However, when nightfall came, I realized that I've went to the wrong direction as the torches I planted the night before were missing. I tried looking around but behold, no traces of light anywhere. (I was still in "peaceful mode".) I walked and walked, and when morning came, climbed a mountain in an attempt to look for my house. (Beside's having a very tall pillar above my house, I also made a very tall pillar of light in an adjacent mountain.)
Nothing. No sign of my house. So I kept walking and walking until I reached a snow biome. Then it rained. I realized how hopeless my attempts to explore and look for my house. I decided to make a compass (a compass would lead me to my original spawn point). Since I have no materials for such device, I tried to dig downward to mine some redstone. While I was digging, I fell into a deep, underground abandoned mine. I explored this mine and found valuable things like ores of gold and iron, lapiz lazuli, emerald, diamond and, at last, redstone. Along the way, I also took some fences and built a small crafting table near a ledge. There I built a compass, and used "pillar jumping" method to get out of this very deep abandoned mine. After plating 64 blocks of cobblestone (therefore the mine is 64 blocks deep, more or less), I reached a ledge and, from there, dug my way up. After finding a layer of dirt with water dripping, I dug towards a different direction. After digging the last block of dirt, finally! Sunlight! I finally got out of that mine.
I hurriedly walked towards the direction where my compass was pointing. I bypassed mountains, desert biomes and seas. Then, when nightfall came, I finally reached my original spawn point marked with a chest and three torches. I didn't know that the game gave me a chest when I first spawned. (When I first began playing, I didn't see that chest and immediately wandered off.)
From my spawn point, I'm no longer a lost nomadic soul. I know where my first (now abandoned) house was. I walked towards it and seeing the tall sand pillar with a torch on top renewed my hope. I finally reached my first house. When morning came, I walked towards my current house in the plains just on the outskirts of the desert biome.
Finally, upon reaching home, I rested.
Aftermath:
The next day, I decided to build a huge arrow in the sand that points to my current house. (Since the compass would only lead me to my original spawn point)