Chronic Fatigue Syndrome Support Group
Chronic Fatigue Syndrome (ME/CFS) describes a sense of exhaustion and post-exertion malaise, even when you have gotten enough rest and sleep. The disease is characterized by six months of incapacitating fatigue experienced as profound exhaustion and extremely poor stamina, and problems with concentration and short-term memory. The cause is unknown, but it is a...

Well, those and D-ribose; I think that's helped me quite a bit. You might want to try that. I get mine from swansonvitamins.com (http://tinyurl.com/o5ddok6), but there are lots of other places you can get it that might be cheaper. Help me out here friends, where else might it be found? I pay about $29 for 4-6 weeks' supply.
If you try it, the recommended dose is 5 grams (not mg) 3 times a day for three weeks, then drop down to twice a day. Rinse and repeat.
That's what works for me, but I'm retired. I have no idea what it must be like for you, brave girl. Best wishes and stay optimistic as much as you can. This illness is bad enough without feeling bad about it too.
Do eat only good food, your body needs nutrient dense food to work with, junk food is just that, junk. Meat, veggies, fruit and grains (if your body tolerates grains). Also stay hydrated. You'd be surprised how often you can be extra tired just because our bodies are so worn down they forget to tell us to drink up!
Wishing you all the best. This illness does very often have remission periods. I've had some up to 2 yrs so don't give up, just realize it's a part of your life now and some days it will make itself known more than others.
I hope all the work being done using us older folks as guinea pigs (the cfs blood bank projects, etc) make it so that you are healed soon! Even if it never helps us, if it will help the next generation, then it's all good.
Another little helpful hint that might help you from reinfecting yourself with whatever bug is going around. Fighting viruses drains the system. Soak you toothbrush in hydrogen peroxide after every brushing.
Hope you find some joy in going to school. Hang in there.
CFS has been redefined in the US as Systemic Exertion Intolerance Disease because of the post exertional malaise. In the UK we are horridly backward and the NHS largely treat it as a mental illness, which has hurt a lot of people.