Hello. The photo is a little hard to make out some of the lines. Did you draw and underlying guidelines to help you before you went straight into your final lines?
#Anatomy
silver bay
jovial pollen
In my case, it helps to deconstruct the poses mainly into cubes; this helps with proportions and three-dimensionality in the drawing. Before adding features to the face or hair, try to find the silhouettes of the poses and deconstruct them, then reconstruct them with simple objects like cubes, cylinders, etc.
Also, try starting with easier poses; if you find it difficult to draw the cubes, you can trace them over the photo first to get used to it.