Why do I get a runners stitch AFTER I run?

I went running around 7 in the evening and woke up the next morning with a really bad runners stitch that stayed there for the whole day. I have gotten this before and I want to say that running is what made it go away last time, but this is day two and I still have it. It doesn’t feel like a pulled muscle, it feels just like a stitch…but I’m not running. I feel it all day. Just going over bumps while driving can cause it to hurt.