There are many times I sign a painting only to find out afterwards that it needs more work. That's why it is a great practice to have a few ways to crtique and check the work.
One way is to turn the painting upside down. This helps you spot problems with the drawing and it gives you a different perspective to see how the light falls across the form.
Another check is to look at the painting in a mirror. This reverses the image, now everything on the right side is viewed on the left. Does the composition still hold up?
I also like to take a photo and check the progress without color.
Now that I showed you what I have checked. Can you spot the areas I need to go back in and fix or touch up?