Can I be pregnant?

Today when i woke up I was felling dizzy and also having a headache and a nausea. I had sex almost a week ago but he didn't remember if he pulled out on time so the next day i took a plan b(because acording to this app there were 17% chanses of pregnancy). Today i also had a brownish discharge (my period should come in almost 9 days). I am very scared and i don't know what to do(idk if that can be implantation bleeding or not..). Is it possible to be just my period or am i pregnant? Please help me🙏🏻

The discharge is starting to look more and more like blood.