My period is two days late.

About 17 days ago my boyfriend and I fooled around, but the only thing that made contact with inside me was precum. And it only went about an inch inside me. I washed myself thoroughly directly afterwards just because I was paranoid, and wanted to do literally anything that could remotely prevent pregnancy. Two days later I took an emergency contraception (plan B or morning after pill) and I read that it can make my period early or late. It was supposed to be here two days ago, but my cycle isn't super regular anyways. It always ranges from 1-3 dates that it is to be expected. But it's about 3 days late now and I'm just worried. Is it the pill that's making it late or is it that I'm pregnant? I have had literally no pregnancy symptoms or menstral-related symptoms, other than breaking out in acne about a day after taking the pill.

Please help me out! And please be nice. I'm not uneducated, I'm just worried.