Have you tried setting up a character sheet? With front, side, back, and maybe a 3/4s view? Style will always naturally evolve, but things like that will help to remain consistent.
I personally do see style jumps as a little off putting--so I think it would help to choose a style, both in linework and coloring. That doesn't mean you have to be married to it forever of course, but having a scene or even a chapter remain consistent looks better imo.
The biggest inconsistencies I see with her is her nose, the cheeks/jaw(?), and the coloring. Sometimes eye spacing. I think the nose is the most critical though? Like, in the images with her hair up, her nose is higher than in the ones where she has makeup on. And I think BECAUSE the nose is higher, you end up drawing her face shorter and her cheeks fuller.
If you do a character sheet (even just headshots) draw the front, then on a layer behind it, make straight lines across the canvas for key features: hair line, eyebrows, eyes, nose, mouth, chin. Then when you draw the side view, you can draw it so everything is lined up. If it looks wonky, you may need to adjust the front view a little too... but it's a good process to go through, because it'll make your characters look more like they occupy 3D space, if that makes sense.