Can you get pregnant and still bleed like a normal period?

So I got my period yesterday and it was a day late no big deal. But I continued to feel nauseous so I though why not take a test anyway. So I am 15dpo but I have had my period for a day now and it's pretty heavy.. Is it possible to still be pregnant even with a period because It looks like I have a faint line on my test. I didn't use FMU it was in the afternoon so I'm going to retest in the morning