When/How did you know your spleen ruptured?

Mostly curious. I have been very sedentary and easygoing since my diagnosis (most strenuous activities I've done are gentle Spring walks around the neighborhood and doing my laundry), and have (hopefully) gotten past the anxiety that thinks every new pain is my spleen rupturing.
What I'm wondering is, for those who had splenic rupture, how did you realize it what had happened?