Hi Fynn. Nice works you have here!
Nice attempt on the female head. Looks better than my first few goes thats for sure! I’m just a student myself, but I do see a few things to note.
First off, if you arent using reference you really should.
I think the side profile is whats throwing it off the most. A lot of the features are sitting too flat on the front of the face. Just google image female profile and you’ll see a ton of great examples. The overall mass of the nose should be 1/2 on, 1/2 off the face if that makes any sense. The barrel of the mouth also needs more fullness and especially the lips. The bottom lip should be more full, but the top lip should protrude slightly more. Some work on the cheek bones and the zygomatic arch extending back towards the ear will greatly improve both the front and side views. You should also consider a smoother curve back for the jaw line. Also the ear is tilted forward when it really needs to tilt back.
All in all you’re on the right track. I’m attaching a profile pic I found online. I sketched in lines in to illustrate some of these areas. The blue line illustrates something you should look for in your work. With most people if you were to draw a line from the brow ridge to the cheek bone it would pass right over the outer edge of the eye ball. Just something to look for.
Hope it helps!