Good work on getting the features to sit on the same horizontal tilt. I do think the length of the thirds of the face are off from each other. Double check those measurements and also compare the width of the head to its length. That is another very important relationship to get correct as possible. Good work and keep going!

This is a good start! I can tell you're trying to focus on the structure rather than just drawing outlines which is great to see, definitely keep that up! I think you may have jumped ahead a little with the details and shading though. The overall proportions of the head are a little off, you've elongated it vertically a fair amount, which is causing some strangeness especially around the mouth area. I would recommend setting aside shading for later and spend some time focusing just on drawing the large forms of the head in accurate proportions and perspective. You don't even have to add features, just doing simple mannequin heads is great exercise and faster to do than a full portrait. If you make it a goal to do 10 of these a day you'll make huge progress in a short time. Keep up the good work! :D

Good job on the study. First thing I’d keep in mind if I was you is not relying too much on outlines, especially the right side of her face which should have the light side against the dark of her hair doing the work of defining the outline. Another thing is value, and I think your tools may have an effect but you’re not going dark (or light) enough with your values. When I squint my eyes from farther away, the entire piece just morphs into one big gray of the same value. The darkest thing is probably the outline of her face on the right. Make sure to look at the reference image with your eyes squinted and judge if the values of light and dark is accurate. Simplify those values with bright, medium and dark values and work from there for much more defined values. If your pencils/paper aren’t allowing you to go darker, I’d get a softer pencil lead and/or get a less rough textured paper. Proportions come with practice and you’re off to a good start, I’d watch the eyebrows since you’re relying on guide lines making her eyebrows attach to the top of her nose and it just doesn’t look right. I’d make sure my guide lines are super light in the early sketch phase when planning out her proportions to avoid visible guide lines like this.