So 8 days ago, my girlfriend gave me a blowjob, to which I came on her butt. There were 3 blobs of semen, which I wiped off with a tissue. Around 1~2 minute later, my girlfriend and I went into the shower to clean off. Is there a small chance that there could be some SMALL amount of semen that could move through the warm shower water down to her vagina, and somehow get her preg? Because of this fear my girlfriend took a plan B pill (One step) the next day,(Before 24 hours) and it has been 7 days since then. My girlfriend told me she experienced light bleeding, breast pain, and cramps in the past 3 days. Does this mean that she is pregnant or would this likely just be a side effect of the plan b pill?