HippiMom2 hit the nail on the head with exercise, and I should have stated this as well.
The point in exercising when you feel like this is not to lose weight, or compete by any means, but rather to increase oxygen in your body. It also helps fight depression and stress with Serotonin and Norepinephrine (Chemicals in your brain) that can be increase when exercising.
As HM2 said, start out slow. Do what you can do. Even a completely healthy person shouldn't start out running 5 miles a day. Work your way up to it. You'll find with time, it will become easier for you, and you'll be in a routine.
I remember when I use to have explosive energy. I would do Martial arts, lift weights, and run. If I didn't do these things, I felt like I was missing something in life.
It's all about habbits. There are good habbits, and there are bad habbits. Don't confuse this with obsession. Obsessing over anything can be bad, and lead to something you really don't want. Back to habbits though... you need to get yourself into the habbit of eat healthy. try to eat 5-6 meals a day, every 3 hours. This will also help stablize your blood sugar levels.
Your carbs can be.... Whole grain brown rice, 100% whole grain bread, rolled oats (not the sugar kind), Yams/sweet potatoes, Lentils/beans. Carbs can also be found in fruits and veggies, however fruits have a lot of natural sugars that can still play with your insulin levels, so keep that in mind. Pink Grap fruits are one of the best fruits you can eat, and Broccoli has the most micronutrients availble.
Your Protein can be.... Fish, chicken, Red meat, eggs, and various protein powders that all include some benifits from the others (Whey, Casein, Soy, Egg).
Your fats can be .... Nuts, all natural Peanut butter and Almond butter, olive oil. Heck, I even eat mayo sometimes.
Remember that with Fat, there are 2 great types, one semi great, and one bad.
Trans fat is the one to avoid. It cause bad cholesterol, and will lead to heart disease. The FDA now mandates that all products show trans fat if it's in the product (yay for us :) )
Saturated fat is the on semi great. I say semi great because too much of it can be bad. You need to keep a balance of this in your diet though. It should be 1/3 of your fat intake daily.
Poly and Mono unsaturated fats are the great ones. They help promote healthy LDL (Cholesterol). Remember, only so much though.
Wow... I ranted for too long. :)