You might have been fine last week and its catching up on you (cumulative effect). A preWO snack is just before the workout, I usually eat it within 1 hour before and consists of protein & fat, a boiled egg works well or chicken & mayo or avocado. A postWO snack is the most important out of the 2, that should be protein & starchy carb, like chicken & sweet potato, no fat. Don't eat fruit before or after, I say that because lots of people want to eat fruit and you don't want to feed your body sugar, you are training it to be fat adapted. The postWO snack should be eaten right after your workout and it only has to be a few bites, so as soon as your done at the gym, or in the car, before your shower, something like that but usually within 1 hour. Then you eat your full breakfast, it can be shortly later, that's fine. Make sure both of these snacks (they are not meals) are in addition to your 3 template meals. A moderator might have some other suggestions. BYI, make sure you are drinking the recommended amount of water & taking in enough salt, that can also effect your energy. Hope that helps!