"Or consider adding a health mechanic where you run into more traps or wrong locations and you lose health. "
Funny you mention that but there IS a health mechanic and you got the "Accident" ending because you ran out. The music changes subtly depending on how much health (horror points) you have left. Leaving the lights on for example costs you horror points because the ghost forces them off, giving you a scare.
I had originally planned on making the phone something you could manipulate and hover over interactable objects before checking them, but I ran out of time and energy. The cell does tell you when you're in the doll's room.
Part of the game's problem is that the mechanics are maybe too hidden. I'm currently working on redoing House in Hellworld in RPGMaker to make said mechanics more obvious, and if I revisit this game I probably won't have a kid protagonist since in my world build most ghosts and faeries leave children alone.
If you replay, without spoiling there are 4 possible phone alerts and only one indicates the presence of the doll. The others hint at a possible horror you can encounter.