@mollylgm Welcome to the site!
I'm not familiar with the book, but I'll offer my insight.
It took my a while to figure out that the character was actually siting in a sink (I thought she was at a table and there was a placemat/table setting in front of her), but after zooming in I now see the sink she is sitting in. I agree that suggesting the setting/sink is better than just blatantly showing it, but right now, it's a bit too suggested.
You also state that you're aiming to go for a more detailed style, and I can definitely see that at play here.
In terms of perspective, I actually think your image holds up pretty well; there are planes that seem a bit off (the section of the sidewalk in front of the transparent window, for example), but nothing that breaks the image, at least to me; one thing I would suggest, though, is consider adding thickness to the bricks that make up the wall, as they look flat/paper-like right now (though maybe they are that thin in the book?). That would make the wall very congested, though, so maybe a different brush should be used for the wall? I'm not really sure.
I've got a couple of suggestions that could help make the image better: consider zooming in on the character and/or making every other surface more detailed except for the window/interior/character/sink. Either method should allow for more emphasis on the character/sink through the method of cropping (not too much, but I think some of the background adds negative space that isn't entirely necessary in terms of composition) and/or increased contrast (right now my eyes consistently look at the sidewalk, as it is so much lighter than the rest of the image; adding some texture to it might negate this).
You've got a good start and I think the composition in general works well. Some added detail and trimming might just be all you need to make this piece a stellar one! Keep working on your perspective, too!