My bf and i had unprotected sex. He peed before putting it in and pulled out before he came. This is my least fertile week, I get my period in 3/4 days. Should I take plan B, its 11:37am 9/29 right now and we did it at 7pm 8:28 last night its been less than 24 hours. Should i just wait on period or take plan B

Please help, we have been together for almost 2 years and we have never done something like this. He was only in me for like 30 seconds.

*update** i took plan B