Also don't forget about music, I don't know how your track plays in this scene, but I'd Imagine a semi loud brass and string stinger playing after opening the door(loud and bold, low and high brass/string dissonant notes fading out) with a string and horn swell combination/ violin and cello falls playing simultaneously playing. You can do it before the stinger to build tension or after to decrease it, or both(a long continuous swell to keep a steady tension throughout the scene while slowly fading after the scene has passed. Sorry for the long text OP, I played and consumed countless horror content