French fries

Riding in a van with two coworkers I don’t necessarily care for. My brother was driving the van and I was sitting close behind him talking to him. Somehow I ended up with two cheeseburgers and 3 small fries from McDonald’s. I think I asked my coworkers if they wanted it and they refused. Next thing I was offering the food to my younger sister and she said yes but she wanted to see how the cheeseburgers looked. As I was unpacking the bag of food to find the burgers, she suddenly changed her mind and she was upset. Then I became upset because she watched me carefully packed the bag of food prior to her asking for it. I was annoyed because as I was trying to put everything back in the bag, the French fries were falling everywhere and I felt like she intentionally wanted to upset me. I said you watched me put everything in the bag carefully and you change your mind while I’m taking everything out the bag for you? And what’s the bad attitude for?