Hi Nils, I like your drawing, it really captures the models energy well. I made a quick diagram to show you some of the things that I think your drawing could benefit from. I hope it helps :)

I have a few notes for things that you could work on but first I'll say that you chose a pretty difficult reference picture and that could be the cause of some of the issues I'm about to mention. I'd usually recommend choosing a subject that isn't wearing make up because make up is designed to trick the eye and alter how the face is perceived so it can become difficult to tell what the actual form of the face is and what's just make up. Also the resolution of the image is kind of low so that might make life hard when you're trying to render little details like in the hair. Also I'd try to find something with more dynamic lighting for the next one, this ones lighting is a little flat so it doesn't show a whole lot of form. As for the actual drawing I think you could maybe bring up the high tones and highlights a touch more to give more of a separation between the lights and darks and build more contrast and depth in the image. Secondly I think there's some proportions going a little off on her right eye (our left), that eye doesn't seem to be quite the same shape as in the reference. I think it might be a little too low and small. Sometimes getting a ruler and lining up the features can help, it also helps with just figuring out the general perspective of the face too, seeing as most of the features are going to align parallel to one another (eye to eye, nostril to nostril etc) if the face is in a symmetrical expression Final Thing is the hair. Overall I feel like its far too busy and could be simplified down a lot more. As I mentioned earlier the resolution of the reference doesn't help, I can barely make out the strands myself. But just for future reference its best to try and simplify the hair down into 'ribbons' rather than trying to depict every individual hair and don't be afraid of allowing some parts to get lost in shadow like on the right side of the her face in the reference, that way there isn't so much detail detracting from your main focal point (the face) Been studying Hair allot recently and I found this video that really helped me a ton https://youtu.be/w0Qh4Cu5ecM Hope that helps in some way