The sand is very dangerous and can cause the issues you are seeing. It can cause corneal ulcers, skin problems and intestinal impactions. This is graphic, but it explains about sand: http://www.petzoo.co.uk/product_info.php?products_id=467 and this one:
We can try some first aid, but the Leo will need to see a Herp Vet. Please give the leo a soak in a 50/50 warm water and Pedialyte solution for 30 mins. While in the soak try to remove some of the retained shed as well as gently massage the abdomen to get a stool passed. You can sue some plain saline in the eyes.
For feeding please mix some plain meat flavored baby food mixed with plain calcium and drop on the snout. Do not force feed. The Leo should help the Leo by allowing it to lick the mixture.
The Herp Vet will have to remove any retained eye caps and do a fecal to rule out parasites. I am going to give you my care sheet to help with the husbandry. Joan
Leopard Gecko Care Sheet
The Leopard Gecko is originally from Pakistan, India, and a few other countries in Asia. They actually live on hard rocky outcrops and they are nocturnal (active at night). They prefer temperatures between 82 and 88 degrees all day and night. They grow to between 8 to 11 inches. Leopard Geckos are available in a wide range of colors and patterns which are the result of selective captive breeding. These include albino, ghost, striped, jungle, Leucistic and high yellow. These colors have been made possible through selective captive breeding. Leopard Geckos make wonderful pets for almost any age person. Leopard Geckos also make good long term pets. They can live over twenty years. Never grab by tail it will break off. Leopard Gecko Housing: A male Leopard Gecko should never be housed in the same cage as another male leopard gecko because they will fight and possibly kill one another. A male can be housed with several females without any problems. I do not advise housing leopard geckos in the same cage with any other reptiles. A single Leopard Gecko can be kept in a ten gallon tank. For a male and a few females a twenty gallon tank or larger should be used. The cage should have a screen lid on top of it to prevent any escapes. Leopard geckos need places to hide and sleep during the day so you must provide a couple of hiding spots. They need a warm hiding spot and a cold humid hiding spot. Just put one hide box on the side with the heat light and put the humid hide box on the side that does not have the heat light. I actually prefer an under the tank heater for heat source rather than a light since the geckos are Nocturnal. For the humid hide box, Paper Towels work well and easily replaced inside a hide box. You can make your own humid hide box from a small plastic shoe box or from a margarine conatiner. Cut a hole in one end of the container and place moist paper towel inside it. The humid box should be cleaned out every week and re moistened. A humid hide box is needed so that the gecko can go in it when it needs to shed. The humidity helps the old skin come off.
Substrate: There is an abundance of products on the market that claim to be safe substrates. All Loose Substrates (Please note the link above) however are not safe to use. A substrate is what you put on the bottom of the cage for the lizard to walk around on. If a Leopard Gecko ingests any of the substrate accidentally, the substrate must pass through the digestive system. Trust me they will ingest substrate, sometimes on purpose. If it does not easily pass through the digestive system compaction will occur. Compaction is an extreme blockage of the digestive tract and is often fatal. Some substrates that I consider unsafe because they can cause compaction are: sand, bark, Calci sand, crushed walnut shells, lizard litter, gravel, aquarium gravel, and coconut fiber. The safest substrate is using paper towels or plain newspaper, non-stick shelf liner , cage carpet or ceramic tile. For any leopard geckos that are younger than six months I advise using paper towels or plain newspaper until they are at least six months old. Calcium sand is not fully digested no matter what it claims. The stuff just does not break down completely. .
Leopard Gecko Heating and Temperature: The cage should be between 82 to 88 degrees all day and night. There is two basic ways to heat the cage. One is to use a under tank heater like heat tape. The other is to use a black, or blue night incandescent heat light. I prefer to use a heat light. For a 10 gallon tank a 60 watt bulb should work depending on room temperature. Place the heat light on one end of the cage. By putting the heat light on one end of the cage it keeps that side warmest and allows the gecko to move to the warmer side with the light or to the colder side without the light as needed to regulate body temperature.
NEVER EVER USE A HOT ROCK, HEAT ROCK, OR ANY SIMILAR PRODUCT. Hot rocks heat unevenly and are notorious for causing terrible thermal burns. Do not buy a hot rock and if you know anyone who uses one, tell them to throw it away.
Leopard Gecko Feeding: Leopard Geckos will do very well on a diet of mealworms and crickets. I like to provide some variety in feeder insects to create a more balanced diet. Feeder insects I use are silkworms, mealworms, roaches and crickets with the legs on one side of the body pulled off. Crickets will bite your geckos while they sleep, these bites are prone to infection, so if you pull off one side of their legs then they cannot move around the cage and get to the gecko and also this prevents the crickets from climbing out of the cage. Gut load feeder insects for at least a day before putting them in with the gecko. Feed geckos insects that are not larger than the width of the head of the gecko.
Adults can be fed superworms, though I advise only feeding a couple superworms at a time. Leopard Gecko Vitamin/Mineral Supplement: For young geckos dust the feeder insects every other feeding or place a small feeder dish with supplement in it and some mealworms in the cage. For adults and babies place a shallow dish or a plastic lid in the cage with a teaspoon of calcium powder on it. The gecko will lick the calcium powder as needed. You still need to dust feeder insects every other feeding though with a vitamin supplement for young geckos. Adults use vitamin supplement once a week. Leopard Gecko Water: Use a shallow water bowl, fill with water as needed. Remove bowl from cage and clean out weekly.
Do Not Feed Pinkies