Birth control causing IBS-D?

Hi all. I just started Yasmin about a month ago and am now on my week of placebo pills. I'm concerned because ever since I started taking the pill, I've had very soft watery stools...and its been occurring more this week (the placebo pill week) than when I was taking the active pills (though it did occur during the active pills as well). I was just wondering if anyone else on birth control has had a problem like this relating to IBS-D symptoms and how they have dealt with it. I am going to try watching what I eat (eating more insoluable fibers) and excersizing more...but will the IBS-D go away within a few months while my body gets used to the pill? Or will I always have this problem while taking the medication?