Hello Bogupala,
I can tell that you had a lot of fun, and probably had a few personal breakthroughs with this piece. And I congratulate you on that.
I can tell you are proud of it and I don't want to trample that. But you have some room for improvement here that I want to share with you so that you can take it into your next works and be proud of them too. I found this piece interesting so I wanted to help, and say, Well Done!
Critique 1: The first thing that I thought was that the piece was a little flat.
Theory: White for some reason always flattens a piece although in theory it should really pull the elements that reflect it towards the viewer. White has to be the brightest thing on the picture but also has to have a shadow equally in contrast as dark. When we have to paint the sun what other tool than white do we have to translate how bright something like the sun is?
Solution: It looks like you used the dodge and burn tool some places, and not in others, but also used white to paint. And that is fine, use the tool if you need to pull out some great hot colors. In the paint over to give off the effect of a neon color I used the brush tool set to Color Dodge in the top left with bright magenta with a plain an airbrush in varying size. I'm not saying never use white again. Just use it sparingly and know that white is the complete absence of color.
Critique-2: The second thing I felt was a little distracted. And when I say distracted, I mean I took a while to figure out what was going on in the picture. I felt there didn't need to that distraction as I stared at the picture to try and figure it out.
Theory: In this day and age if your viewer doesn't get it in six seconds, that's it. They stop looking and move on. What mood or intention did you want to create when you started making this piece or maybe even decide upon halfway through? When we answer that question for ourselves we solve a lot of composition and hierarchy problems early on to lead us to the end of the painting.
Solution: Simplify. Brushes are bloody fantastic. But sometimes they create a maze for us to solve as the viewer. I always ask people, "What were supposed to be the focal points of your picture?" And encourage them to make the viewers eye circulate back and forth from those focal points using contrast. Contrast of edges, value, counterchange, color and shape.
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I tried to simplify and bring the viewers eyes to her eyes here since this is technically a portrait piece. I also softened the face a bit and cropped in. I didn't take time to correct texture.
This paintover is not my best but I tried to illustrate some of the things I talked about here. You made an extremely great challenge for yourself and you should be proud of it.
As always take any critique with a grain of salt as I am only one viewer, and am critiquing based on my biases and tastes. I am not preaching holy script here. One teacher will love it and another one tear it apart. Only you know the best and truest knowledge of what you wanted to represent.
Edit: Redone paintover.