As far as the "snappiness" is concerned, it took me about a week before I came out of it. My wife almost asked me to quit the first week because she said I was so irritable it was hard for her to be around me. But she toughed it out, and after the first week, it quickly went away and all of a sudden I felt great! So hang in there, it really does get better.

You may want to go back and recheck what Fitday defaulted to for amounts. What you have listed there doesn't look even close to 2,000 calories. If I had to guess, I'd have to say that it might not even be close to 1,000.
Fitday will sometimes default to some very strange amounts like "1 cup of egg" and "1 cup of mayonnaise or butter" when you really had much less. If you don't watch those defaults, you could get quite a shock.
I also agree with all of the above...you need veggies; at least 3 cups a day, and increasing the fat will help with hunger.
Also...are you taking any kind of supplements? The dizziness and muscle aches could be due to low potassium. Then again, if the above has been a typical daily menu for you, you just might be feeling cruddy because you aren't eating enough!

Edited to add:

1 put your menu listed above into Fitday, allowing for 6 oz. ground turkey and 150 calories for the Atkins Crunchers and came up with just under 1,200 calories.