So embarrassing, sex,pregnancy no bladder control

Hi ladies I'm posting as secret because this is so embarrassing. I'm 19 weeks pregnant. Yesterday me and my fiancé were doing the deed and when I was about to climax I peed, I mean this wasn't "squirt" it was a full on wee. What's worse it's uncontrollable, I didnt even know I was doing it untill I started feeling soaked. My fiancé was really good about it and helped me clean up. I've never done this, is this a pregnancy thing or is my bladder just shot now. Please tell me his has happened to someone else :(