pretty good without references

I know alot of strong artists that still use references, so don't worry about that you should still use them. i myself have folders and folders of reference photos .

About the picture it self if you can notice what you see as errors in your own work your heading in the right step in getting better.

A Critique of the work if you dont mind : Although the anatomy is off, some of the things are correct, if you were to drop the portion from her buxom to the head down at the bend where her rib cage is i would fix the look alot.

Really thats the major problem in the picture, but anything else just needs to be touched up, like the leg and shading but other wise its a good piece.