In image 1, you can see that the camera's flash has cast a sharply outlined shadow on the cat's forehead from the edge of the blanket. If you're familiar with eye anatomy, you'll know the cat's eyelid doesn't lay flat against the iris, the two are separated by the clear cornea. This separation allows the cat's the eyelid to cast a sliver of a shadow from the flash onto the surface of the iris, much like the shadow of the blanket on the forehead (see also image 4A). Since the cat has dark skin outlining her eyes, your eye is tricked into thinking the black outline on the cat's upper lid is also skin pigment, and not a shadow.
The vivid green of the cat's pupils is the flash reflected from the retina, at the back of the eyeball. This reflected light comes in a variety of colors, typically based on the pigmentation of the animal. Since it's a light reflection, it won't have a shadow cast across it. To learn more about this, check out this interesting site: Reflex Colors
In image 3, I've zoomed in on the photo and outlined the upper lid from the corners of the eye. If you look closely, you'll see some hairs hanging over the upper lid just below the outline. They are also visible in image 4C. These are the cat's eyelashes. In this photograph, the resolution is low enough that the pixels overlap some, and so the eyelashes give the illusion that the eyelid is more closed than it is. The green pupil reflection is bright enough to transmit through the eyelashes.
Finally, the uneven values in the green pupils are the biggest tell for me. In order for a photoshop artist to fake this, he or she would have to be very knowledgeable about eye anatomy or have cut and pasted pupils from a photograph with identical resolution. The gradations indicate a reflection from the curved surface of the retina, and the brighter specks (4B) are probably light hitting floaters within the vitreous. So it makes no sense to me that an artist would go to such great lengths to create such realism in the reflections of the iris, and yet overlook such obvious "mistakes" as painting or pasting a pupil over the edge of an eyelid.
My conclusion is this photo has not been altered in photoshop.