Yeah I was originally thinking of some combat, although with 3 hours I'm not sure. I might update the game later with some keys and doors, I think that could be good, and might also help direct people towards where they need to progress.
If you make it to the ending, there's no way out (so you can't wander back into the dungeon), so I suspect you didn't get to the end. That's also the only portal that "changes", everything else is static