Cloudy urine

Can anyone tell me what can cause cloudy urine? I've been drinking A LOT of water the past few days and my urine has been clear up until a few minutes ago I had to pee and couldn't see the bottom of the toilet because it was cloudy white. It didn't burn when I peed but I'm curious as to why it was so cloudy? I've noticed this a few times before in the last month or two. I got tested for a UTI last time and was negative and have been treated for bv and yeast infection recently. I also had sex last night (no condom) and my boyfriend came inside, could this be it?