@countrygurl32 So, your body's choice macro to make energy for the body to move and perform exercise are carbs.
You carry carbs in your muscles, blood, and liver. As you workout, you deplete these carbs as you make energy. You have a finite amount of them on hand, and while fat is also an energy source, it actually takes your body a long, long time to utilize it. Once your carb source starts to run low, your body starts to restrict your muscles, a bit, because your brain also needs carbs to function. It is higher on the hierarchy than your muscles.
In order to have a second session, you need to restock you body with these carbs that it just ate up in your workout. Your body is low on it's primary fuel source to perform any kind of movement.
Now, in terms of macros, there are carbs, but there are also FAST digesting carbs and SLOW digesting carbs. Rice cakes and gummy bears book it to your blood stream, fast, and replenish those carb storage banks well.
Slow digesting carbs can take a while to get there. Fruits, veggies, etc.
Additionally.
Fats and fibre ALSO slow digestion.
So if you are in a state, where your primary fuel source is low, and then you are eating your first meal after exercise to replensih yourself, that is a bit high in fibre (blueberries and fruit), and fat (the nut butter), you might be feeling tired.
NOW.
This might not be why you're feeling tired. But it is something to consider. Rice cakes should sit well, and could help you a lot having them an hour prior to working out (hate to give advice like this, out of my scope, but if you're feeling so low, it could be worth a low risk try).
I am just giving a sparknotes version of this wonderful teacher's hour long lecture.
Please watch if you want a more in depth understanding