Still a beginner

I just learned I am probably a pre-diabetic. Other changes happening as well. I'm still hoping this program will work if I stick with it long enough. In the meantime, I still experience fatigue. And I get really hungry. Timing is an issue. I don't want to eat every 4 hrs..
I am exercising. Nothing strenuous, just 30min walking daily and 2-3 times per week, 30 min biking. And I'm not pushing it, just continual movement really, but I can tell a difference. I read in one of the books, that if you exercise you need snacks. But I wonder if I'm getting enough "browns"?
FYI- I'm still working on breakfast. I use the protein shake often for breakfast,, but I'm hungry 3 hours later. If I eat a snack (is cheese toast ok), it triggers a serious hunger and spoils my appetite for lunch. Perhaps I should eat by the clock, with only measured amounts.
Every time I blog, it seems I have SO many issues. I'm really a mess. Maybe it would help to blog more regularly so I stay more aware.

Thanks for any input anyone may have.

Still a beginner, but determined to press on.

Rachel