Hey SkillerS! I deleted your comment on the game page to avoid spoilers ;). Hope you don't mind. The "galaxy stuff" is not the secret ending, no. Here's a hint: why do tomorrow what you can do today?
Thank you for playing!
"why do tomorrow what you can do today"? That sounds like a minor shortcut. I managed to skip a brief cutscene, but if that's not it, I don't know what it is. There's really not much to do there, and I tried everything. The surprisingly interactive bathroom door is intriguing, and a bit glitchy (in some ways... in other ways, it's one of the least glitchy videogame doors ever). But you said it's not a coding error, so no clipping out of bounds, I suppose.
Oh, by the way... there's a bug that prevents you from picking up items... in a green room. So that's preeetty bad. I'm not sure when exactly that happens, but there's also a late doorway that makes carried items vanish, so maybe that's related. Maybe I'm somehow carrying and not carrying an item at the same time.