I peed my paints in the middle of Walmart

So every once in a while I get this sudden urge to pee and if I don’t get to the bathroom in like less then a minute I pee my pants. Well today I was in walmart and I kinda had to go pee so i took a step to walk to the bathroom and I peed my paints right there. I don’t know what’s wrong with me. I’m not fat or unhealthy (I workout every day) I’m not old (I’m 17) I don’t have Health insurance so I can’t just go to my doctor (I don’t have one)