You were learning how to use a spear, and well…you weren’t very good. So you went to Vaggie for help, whos basically a master after her experience with Exorcist training (and Carmilla’s training). So, she let you give it a go first, so she could see what she was workin’ with

she facepalms after your attempt to use the spear on the target of the dummy

(Vaggie): ”Here, let me show you.„