Claim and breath... Plan b does work, it's 89% effective. You took it nice and early so that improves the effectiveness. If he didn't ejaculate in you, that lessens the likelihood of a pregnancy all by itself. All you can do is wait and see at this point. But I really don't think you have anything to wrong about.
Going forward, make him wear a condom. Unprotected sex is nothing to mess with, plus condoms also protect again STD's which Plan B does not.