Taken Aftera (Plan B generic brand) and this happened.

So I'm panicking! I have taken plan b name brand before and this has not happened to me. I actually took the pill a while ago, maybe 3-5 days ago if not more. And I was walking down my apartment hallway and I PEED MYSELF A LITTLE 😱 is this a sign of early pregnancy? Is this even related to the pill? Or could it be a more serious issue like a bladder infection? I'm 19 years old. And I feel pressure near the bottom of my belly. Even though I do not have to pee. 
(Yes I know none of you are doctors, but I just want an opinion on what I should do or if you guys have any idea what may be happening because money is tight right now!)