What's wrong with this conversation?

Me: Alyssa, you've already had 3 fruit snacks today, you're not having anymore.
Alyssa: (while holding fruit snack) I'm just going to take this upstairs to my room to look at it.
Me: If you eat that you're going to be in very big trouble.
Alyssa: I'm just so hungry!
Me: I'm going to go upstairs to change my clothes and then I'll find you something to eat.
Alyssa: NO!
Me: You have three choices: You can eat that fruit snack and get in very big trouble, you can eat nothing, or you can wait 2 minutes for me to find you something to eat.

Guess who is in very big trouble and proud of it. At least she admitted to me that she ate the fruit snack, right?

I probably shouldn't have even given her the option of getting into very big trouble.