The weirdest thing happened to me today in single player.

I finished building my nether portal and traveled through it. After harvesting some netherrack and glowstone, I stepped through the portal that I exited from in the Nether and was ported into the overworld of ANOTHER GAME THAT I PREVIOUSLY DELETED. Thinking that I couldn't get back to my current game, I deleted the save. In retrospect, I should have tried killing myself and see if I would reset back to my bed, but I totally neglected this possibility at the time.

Has this happened to anyone else?

Nope. Buuuuuut.... That sounds awesome! You could've probably took supplies out of your old house and see if you can go back through the nether to your actual game.

That is one of the weirdest glitches I've heard of. I don't even know how that's possible.

For some reason I imagined you not loading up a previous minecraft seed, but actually loading into Trials: Evolution as you step into the nether gate.