There is only one ending, so you didn't miss anything! As far as my original goals for the game / what story I wanted to tell, it's complete.
I left some intentionally unanswered questions in the story that I felt would either spark the imagination or help feed into the terror (for example, I think it's creepier if you have no idea where Marissa gets her meat. It might be harvested from the monsters, but who knows where it's actually from?).
That said, I am considering expanding the story out and answering some of those questions, either through added content to this game or through new games entirely. Unsure which at the present moment. I think you'll enjoy some of the things I have in store though!
Thank you for leaving this honest review and while it didn't entirely satisfy in its current state, I'm glad you enjoyed it!