I thought I had a UTI, so I tried some ASO. A couple of days went by, and I noticed the feeling of needing to pee after I had just used the bathroom again. It's not painful, more annoying, it's really hard to explain. I also noticed that it happens the day after me and my fiance have sex, along with very minor stomach nausea. Neither one of us has ever had any type of STD, and it just started happening earlier this month. We have safe sex, with a spermicide and have been so for a while now. What's going on?