Pregnant ?

I’ve had unprotected sex and have also missed some of my birth control. The last few days I have felt really nauseous and have had spotting on and off for the last 6 days. I haven’t filled up a pad at all. It takes all day before I even have to honk of changing one. And then other half of the time there’s just a bit of blood when I wipe. At first I thought it was implantation bleeding, but I know it shouldn’t last this long. At this point I’m confused. Plus my period isn’t for another 13 days. And this has never happen to me before.