Better safe than sorry???

No judgement or criticism please. My boyfriend and I had sex last night and the condom broke. He didn't finish inside, but I still think the pull out wasn't necessarily 100%. I started my period today. Would you recommend taking Plan B anyways? (I'm in the process of getting on birth control, so that isn't the issue here. Im talking more in relevance to plan B vs my period being able to flush things out (which I really don't know, which is why I'm asking).)