An objective critique:
1) if this is intended to be a human eye (or anything closely related), there are a great deal of issues with the physical anatomy. The main issues would be these -
- The orbital mass of the eyelids, rather than being the seperate muscles that they are, appear as one ring shaped object. There should be a great deal of seperation - or rather opposition - between the top and bottom.
- The plates of the eyelids appear as though they are turned back exposing the wet pink flesh underneath...where there should be an edge there is instead a soft round mass.
- The caruncula (you know..the pink stuff in the corner of your eye..) appears as a burgundy glob in the corner, rather than the soft pink mass that should merge more smoothly with its surroundings.
In addition, the iris seems far to dark, and a bit tto dull as well. It should be lightened, and there should be a little more visible detail. It could also stand a little bit of a darkening around the outer edge, and unless the person (thing) is standing in near darkeness or on some sort of hallucinagenic drug, the pupil should be far smaller.
And lastly, I would put a greater consideration into the light source. There is no clear definition...but the general lighting would suggest soft light from above, while the cornea and caruncula would suggest a sharp light, one from the left and the other from the right and slightly above.
The technique itself is not bad. The style is somewhat rough, but that is not a abd thing - in fact in many cases it can be a very good thing.
So what it needs from here is a bit more attention to the anatomy, a closer control over the concept of light source, and - most importantly perhaps - an indication that the eye is wet! Your eye is always wet afterall.
Never be afraid to ruin a painting - it's how you learn. It's how you grow. If you do so few paintings that you are afraid to ruin one, then you won't paint enough to learn anyway.