Jack refers to Gwen's pregnancy saying 'Haven't you heard of the immaculate conception?' This is a common error. What he should have referred to was the 'virgin birth'. The dogma of the immaculate conception refers to the belief that Mary (Jesus's mother) was conceived without the stain of original sin. Many people get these two ideas mixed up.
After the monster (as Jack) has fallen on the bed, Owen's gun is empty with the slide locked back. When the camera angle changes and Owen approaches the bed, the slide is forward and presumably loaded.