Goofs

The day after Louise is bitten by the vampire, the fang marks on her throat are not visible.

The second day after another visit from the vampire, the fang marks have disappeared from Louise's neck.

When the doctor goes to drive a stake through the heart of Louise, it shows him begin to pound it. In the next shot, he is still holding the stake above her heart, no blood showing. When he turns away, he is still holding the stake and there is no shot to establish that the stake remains in the body.

Although the cellar was converted into a wine cellar complete with bottles and barrels when the newlyweds renovated the castle, it's odd that no one saw a very obvious coffin in a corner. Considering that now it's surrounded by wine barrels that were put in place during the conversion, it would have been hard to miss. And of course, no one sees it during their "careful" searches in their attempt to locate the vampires.