Plan b

Mykah

So about 4 weeks ago I had unprotected sex and he finished inside me. I am on the pill and take it every day on time. I took a plan b about 5 hours later. My period is supposed to start yesterday or today and it hasn’t. I’ve just had discharge. But last week I was spotting, it was darker tho, like it was old blood or something. Is this normal? What should I do?