So you're still growing and in a calorie deficit daily already--plus you're active. I think it's great you are tackling paleo so well at your age. I would just be careful not to bother with fasting yet. Do that later when you are older. Right now enjoy sweet potatoes, lots of good fat, meat, nuts, berries and I 2nd maj's chocolate.
Also...try not to obsess...good fasting habits can quickly turn to too much fasting and a quick fix for when your diet just needs more quality and better timing.
I would suggest berries, nuts after school before soccer. Also...really good quality hot dogs like Tanka Dogs or just a good kosher brand with some Bubbie's sauerkraut is really fast and not as filling. You could have some coconut milk over some frozen blueberries or make a smoothie. Or you could have some full fat greek yogurt with some fruit and nuts. Sweet potatoes with some coconut oil or butter and salt and cinnamon.
Check out Sarah Fragoso's site and podcast. She has a ton of suggestions for kids your age.
Everyday Paleo
And...you are still a little girl to me too. (That's a GOOD thing.) Don't grow up to fast. Enjoy. Enjoy and stay excited without getting obsessive.