Should I take Plan B?

I posted this question in another Room but wanted to get more certainty.

So Im currently 6 days late for my period and pregnancy test came out negative. About 2 days ago husband and I were having like 3 am sex and he said he was sensitive and might have came a bit, but I remember going down to give him head and swallowing. Anyway, I know for plan B you have a 3 day period to take it. Should I take it even though my period should be coming soon and its after ovulation? Peak ovulation was the 12th and the 13th is when we had sex but it was the last day of ovulation