Pistachios. Can I have pistachios?
Apparently not.
https://www.dietdoctor.com/low-carb/nuts
Like I say, though, it's not hard and fast. The issue isn't carbohydrates qua carbohydrates, it's the glycaemic index. Slow-release carbs in things like oats, nuts and beans aren't what will put weight on you.
You can get pistachios, yes
Also unsalted peanuts or pumpkin seeds to snack on
Your feeling hungry even after a big breakfast situation is unfortunate - sounds like you have a massive stomach :-(