Is Taking Plan B Pills After Unprotected Intercourse Safer?

I had unprotected sex last night and am wondering if I should consider taking the plan b pill. I am on birth control and have not missed any pills, my boyfriend said he didn't cum inside me just near my vagina and we just want to be sure. Should I consider taking the plan b pill or should I be okay?

Also, I spoke with someone earlier who told me that with where I am at in my birth control (white/sugar pills, will be getting my period tomorrow or Friday) that I am less fertile, is this true?