When Licia arrives looking for Giovanna, her hair is up under a beret. Cut to her 2 sec. POV survey of the empty room, cut back to her, with her hair all combed out, and beret nowhere to be found.
A woman's arm is injected with a sedative. Tubing is tied around her upper arm, which is used to cause the veins to stand out. This is only done for drawing out blood. No regular injection needs a tourniquet.
The little portable tape recorders Licia supposedly uses to haunt her victims have low fidelity sound with very limited volume, certainly not enough to send sound echoing down long corridors, as depicted.