Should I take Plan B??

My boyfriend and I never use condoms since we are both clean and I am on birth control pills. We had amazing sex last night for the New Year, and he tried to hold it in so long he ended up blue balling himself so we stopped. I don’t think he got in cum or pre cum or whatever in me, and he doesn’t think he did either.

But I just came off the white placebo pills (if that’s what they’re called) for last month’s birth control, and had the first of the regular pills for this month.

He offered to go get me some Plan B, but I’ve heard that you’re not supposed to take it if you’re on birth control? Should I ask him to go get it for me anyway?