First off, the fact that you did this with only one layer is amazing.
One of the things that doesn't stand out, but adds tremendous grace to this piece is your line quality. The lines are very consistent and dont distract from the color scheme.
Which speaking of the color scheme, with a title like "Burn Inside" the colors that you used do not disappoint. Though I think it would have been better if there was more use of textures to imply the type of material the dress is made of, or for the background, the use of oranges and yellows rather than reds made a great transition between her skin and the rest of the painting.
Overall, I think the strongest part of this is the over-all feeling of gentle sadness. Not overwhelming, but a gradual ache that comes off from this piece.