Yeah, people are saying good things
My main principle with shading is that there is always a difference in the “temperature” of the part of the object, which is shaded. Where there is light, it’s warm (so, thin yellow, orange washed at the very beginning of the painting usually give that vibe), where there is shade, it’s cold (light blue washes give the best result). It might change with the texture of the object, but generally that’s what I was taught and it has not betrayed me yet.
With the flower, blue, mixed with red maybe, so almost purple, but more into red, could be good for the shaded part... Rose color is generally a cold color, so if you add a slight wash of yellow or orange to the parts that are in the light it could add even more 3D effect to flower itself
Good job with making watery watercolour. A watercolour without water is not a watercolour. I find it one of the hardest types of paint to master but I just love it. I had a very good teacher who showed me the techniques of working with it, so now it’s my primary media, when I need to color something
Uh... it’s always so hard to describe colours, I usually feel the color and paint, so oftentimes I don’t even think when I do that. I see and I paint, but then when I need to figure out how I managed to get a certain shade, it becomes a problem :'D