Wierd help

I’ve not played Minecraft for some time, about half a year. So, what I decided to do was to erase Minecraft and re-download it to ensure all modifications, etc, were removed. I opened the launcher and started to update and install, as usual. I generated a world with blank seed and blank world name. Strangely, I happened to spawn in a Mineshaft. I thought I bugged through the walls or something, but I tried mining a block and it worked. So I went exploring the world when I stumbled upon an iron door. I couldn’t find any lever/button to open the door but it looked like it was one-sided. I managed to peak through the door and the first thing I noticed was that the room’s wall & floor were all made of bricks and dirt. I gathered resources and crafted a pickaxe to break the door. The room was perfectly square. Then, out of the blue, blocks rapidly started to break above me and it felt like something carried me up to land. I was in a forest biome before I knew where I was. It was day. The blocks which were broken were then recovered. It was all remarkable. Unfortunately, I didn’t get a screenshot.

This is a true story. Please share your opinions on this.