Confused

My husband and I just started to conceive. And a day before my period I went to the doctors for a pap. They had me take a preg test there(granted I had already gone an hour before but was able to squeeze a few drops) the results came back negative so the Pap test continued. I started to bleed a little bit at the end of the Pap test and thought my period was starting. But since then no more bleeding. I am now 4 days late. I'm not having any signs of pregnancy but I've never missed or have been late before. Has anyone gone through this????