Don't worry too much about how long it takes you -- speed with come with practice. You did a nice job filling in the details and it looks like you followed the simple to complex process. Really focus on the angles of the landmarks like the angle between the eyes, and the angle between the eye and the top of the ear. Finding those angles will be very useful to you in determining the placement of the nose, mouth, and overall angle of the face. Overlaying your drawing over the reference image shows that the angle between the eyes is a bit off, which give the effect of the face tilting in the opposite direction. Hope that helps :)