Thanks for sharing your story and I wish you the best with your plans!
If I decided that I wanted to be a diplomat after all and finished college in my country, I don't know how I'll pull of the additional classes relevant to diplomacy (such as economics and political sciences) because they're given on a completely different college than the one I'll be at if I choose Physics. Self-study looks a bit tough, but I'll probably have to get the will if I really want to be a diplomat. I'll have to go see options for grad schools.
Thanks again, your posts opened up my point of view.