Plan b pill

This is the first time this has ever happened to me but my husband & I had sex early this morning (with a condom) & has he came he started to pull out but I Tensed up a little & the condom started to come off. He grabbed it before it came fully off but as a precaution I took a plan b pill. My glow app (I know they aren’t always accurate as I have kinda irregular flow) says that my first fertile day is today, I took the pill a couple of hours after. Please be nice. I know that condoms/plan b pills aren’t 100% but should I worry?