I've asked this question about 3 separate times but I'm paranoid and haven't gotten a satisfying answer. . More like snarky comments. However I had a little "slip up" recently and had to use plan B for the first time. I know it can mess up your cycle but they said on the plan b website that if your period is more than 1-3 weeks late you may be pregnant. (Almost 2 weeks late) so I bought a test that came back negative. Again on the site it says that if you are over 165lbs it is less effective and if you are over 175 (which i am )it isn't effective at all. I'm at odds here 😩