Accident on mini-pill...

This morning my hubby didn't pull out on time and I'm freaking out. I'm on the mini pill and I take it religiously each day at the same time down to the minute. I've been on it for at least 6 months but my son only breastfeeds once or twice a day now. I'm reading over time this pill specifically becomes less & less effective which I was never told by my dr. Anyone have any clue as to my odds of being ok? Debating the plan B pill but not sure how much I'm overreacting.