To me is sounds lke you are either pregnant, anemic, or both. Anemia is really common amoung women - we loose a lot of blood during our periods and pregnancy and our bodies need a lot of iron to make more blood for us. When you are anemic it means your blood is thin because our body is not getting enough Iron to make more. You feel SO tired all day long and you will keep feeling tired no matter how much sleep you get until your Iron levels get back up. I get anemic during pregnancy and I'm currently just 2 weeks from my due date with my second, so I've been through it twice.
Are you taking and vitamins? If not, atleast get yourself on an Iron supplement. Choose one that has atleast 100% if not 150% of your daily iron dose, and go to the natural health food store and get the best quality Iron that you can. They have a lot of awesoem supplements out now that are called "whole foods" or "raw foods" vitamins and that is the kind you want - the minerals in them are straight from plant sources, which your body can use much better than minerals from the ground. You should be able to get a 30 day supply for about 12 or 13 dollars and it's SO WORTH it to get your energy back!
Getting Iron from food sources is great too, and can help you get your levels up faster. Food that are high in Iron are dark green leafy veggies, brocoli, red meats, liver (yuck LOL), beans and foods like that. If you want a full list type "ron rich foods" into google and a bunch will come up.
A tip: Try not to mix your Iron supplement with calcuim at the same time. Calcuim (think dairy) inhibits the body's absorbtion of Iron so it will take longer to get your levels back up. Instead, take it with something high in vitamin C (like OJ) and that will actually help your body absorb it. You can probably even find a supplement that contains some Vitamin C right in it with the Iron so you don't have to worry so much.
If you start on a supplement it will REALLY make a difference in how you feel. It takes your body 2 weeks to build blood, so don't expect to take the iron pill once and immedately have more energy... but if you take it each day you will definitely notice you feel SO MUCH more awake just a few weeks later! No more being so tired all day long that it seems like all you can do is sleep and al you want to do is sleep, even when you have just woken up!
Oh, and if it is a pregnancy, go get a test and find out. The food aversions make it sound like it just might be that. I am the same way when pregnant, especially in my first trimester - SO hungry but NOTHING is appetizing. If you do turn out to be pregnant, getting on an Iron supplement and a good prenatal vitamin is probably the best thing you can do!