It is most likely the change of diet. My dog went through the same thing, what helped my dog was that I changed his food servings to twice a day, so he wouldn't eat it all at once and within a couple of days he stopped vomiting. If that doesn't work maybe you should think of switching to a more gentle type of food.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.