If you rinsed your hands twice, once with soap, and it was a half hour late, you're really really really good. I mean, if she did get pregnant, it'd be some kind of freaky ass miracle. Remember, there's an 8% chance of a girl getting pregnant when a man fully ejaculates in her. (this is a statistic that's averaged, it'd more or less in certain women, depending on ovulation and sperm count and such)