Mirena and pregnancy. I need advice

I've had for mirena for almost a year now and was wondering if any of you ladies have been or know anyone who got pregnant while having the mirena. I took the plan b pill because I let my boyfriend come in me 2 times but I've never let anyone do that before and he's never done that before so we are both a little on edge. I'm going to take a pregnancy test next week. But I wanted to know if anyone had some experiences like this. I know someone who got pregnant even though they took the plan be pill so I just wanted some words of wisdom from some of you ladies.