My body crashes around 3:00-4:00

IN my opinion.. YOUR NOT EATING ENOUGH in the AM or lunch... since your working out in the AM YOU need to fuel your body more. Snack on healthy snacks through out the day. It seems to help me. I get up that early too and go to school, so at that time IM starving. Just look at how many cals you actually have in your system after your work out.. Hope this helps...

I imagine that you'll get a million posts from people far more knowledgeable than I am....but I'll offer my thoughts anyway. :-)
Maybe you should eat 5 meals a day instead of 3? My brother-in-law is very serious about a program that trains you to eat 5 or 6 small meals instead of 2 or 3 big meals. It might help relieve the fatigue that you're feeling at 3 or 4. My bro eats breakfast at 6 or 7am (mostly carbs), has a fruit or dairy for a snack at 9 or 10, eats a small balanced lunch at 12ish, has another small snack at 2 or 3, and then eats a normal dinner at 5 or 6. It really seems to work.
I've also read on other posts that you should vary your exercise...shake things up a bit. That might help you lose the last 5 lbs.
Good luck!

You really do need to eat more, especially in the morning after you work out. What time do you eat your breakfast? I would suggest eating a snack (your current breakfast would almost qualify as a snack) as soon after your workout as your stomach can handle to replace the energy you just expended and help to repair/build the muscles you are working. With eating so little, when you work out like it sounds like you do, your body has nothing but muscle to consume for energy.

An hour or two after this post workout snack you should eat a balanced breakfast. Another contributor to your afternoon crash is the lack of decent morning protein. While you are getting some in the yogurt and peanut butter, you are also getting a lot of sugar which contributes to the eventual crash. Maybe eggs/egg white omlet with some veggies or turkey sausage.

This will put you on track for lunch. And may push it back a little further to help close the gap between lunch and dinner. You snack between lunch and dinner, while low calorie, is refined sugar which definitely contributes to the crash and hunger. I would suggest a complex carb and a protein (fruit and string cheese, nuts, cottage cheese or even a small bowl of cereal.

All of this should help stabilize your blood sugar levels and keep you full enough to help prevent the afternoon crash. I don't know your daily calorie goal but maybe it needs to go up just a bit. Sometimes being below calories everyday can be a bad thing, especially when it comes to those last few pounds.

I am certainly no expert but I hope this helps.

fluffylove, if you do try it, give it about a week before you right it off as not working for you. I always was starving shortly after lunch and crashed mid-afternoon. Of course I was eating a lot of refined carbs and sugary snacks. From what I have read, eating refined carbs can make you crave more refined carbs...kind of an addiction type of thing that your body does. It took me several days of changing my eating habits (actually more like 2 weeks or so) before I really felt a major diiference. And it was really hard at first to avoid the chips or cookies or other yummy snacks laying around because I the "craving" for them was pretty intense. But I stuck it out for the first time and once I finally crossed that hard line and my body realized it was getting the healthy food it really needed, that's what it wants now. I have always heard that's how it works, but I never believed it until I finally stuck to it long enough.