the other issue with that combo is the sodium. Soup is notoriously high in sodium, and along with the crackers, you probably had more than your RDA of sodium. ( i am a HUGE lover of soup, so i have experienced this many times ).
I am like you when it comes to MyFitnessPal. I’m currently not tracking, but i need to get my act together. I’m always amazed at some things that i don’t think are “too bad” for me end up crushing my allowances for the day!!