I like the artstyle, and the challenge of how tight your resources are caught me off guard, that's pretty well balanced and challenging.
I think some of the sound effects could be more distinct, or at least louder. This is mostly because it's a little difficult to tell what's happening in the other room while you're refilling your energy, and stronger sound design would help the player figure out that information when they can't see it.
Also, consider replacing one of the candle objects with something unique. That may have been because of time constraints, but right now, when the player hears a lighter click in the other room, they can't tell which candle is lit, so if it were a different object then they could make that distinction.
Lastly, there's a weird delay when clicking on the door to switch between rooms. And sometimes when I click on the cauldron to recharge I find myself going back to the other room by mistake. That mechanic could be polished up in general.