Hi, im newb in pixel art and let me know if i did the lighting and shading right because i dont think this is not the way of doing it, idk let me know. thankyou :)))
Looks very nice!
This is very well done!
Are you sure this counts as pixel art, it is so well done.
Usually, pixel art serves the purpose of being used as an art style for a project, like a video game. I think your watermelon looks really good and does well with:
- Recognizability
- Colours
- Shading
And with that said anything I could say would probably be extra things to think about rather than a direct critique of your art.
I have to wonder if you had a reference because of how much it looks like a slice of watermelon. A lot of times people will limit the size of an image and amount of colors using palettes and sprite sizes which allow many objects within a scene.
As far as shading goes, there are only the usual things to ask. Did you think about the light source direction? The base shadows vs the lighter shadows? The reflections from the environment? The light bouncing off the surface and making some of that colour go onto the object?
Here is one example of a VERY simple palette using 4 colours :
Compared to your palette
One tip I might say is if you can’t see the difference in colour in the preview window then It might be an unnecessary colour.
(Preview can be opened in View > Preview > Preview)
Yes, I used a reference because I didn’t have an idea of what to draw or how to start. I looked at fruit paintings and recreated them as pixel art. I will follow your advice about limiting my canvas size and color palettes. Thank you for your guidance! :))
WOOOW! 
This is gorgeous! Great job!