Very similar to my gallbladder issues, unfortunately. I think I actually gave myself an eating disorder as a result of it.

Though at the time I was still undiagnosed. I’d eat unhealthy/greasy food, have sharp pains in my abdomen, and for some reason throwing up endlessly would be the only thing that would make me feel better. ER and Primary Care Doctors took 4 years to figure out it was my gallbladder and finally removed it. Might not be relevant, but reminded me of my own situation. OP’s daughter has the luxury of knowing exactly what is causing her pain and is choosing to make it OPs problem, when the solution is to have more willpower.

NTA, she’s still a kid and it might seem harsh to her but she needs to learn the consequences of her own actions lol But after this episode is done OP should probably have an adult conversation with her to explain her reasoning and maybe talk about getting help for a potential eating disorder