Advice on pregnancy please!

Long story short this guy came in me when I stopped taking my birth control like a little less than a month and he also bought me the generic version of plan B and I took it on the same day, like 10 hrs after, and my period is very irregular so idk how I’m supposed to know if my period is late. Basically idk how long I’m supposed to wait to do a pregnancy test. I’m like freaking out and don’t want kids let alone with this man..