Yep! You have to get enough protein... A breakfast that's only carbs, with no protein or fats, will leave you light headed by 10 a.m.
archy's examples are good!
navywife, you might check your calorie counts. It looks like you might be pretty low on calories for the day, and that might make you feel sick--you could have hypoglycemia.
We can always make better choices!
Jay