My period is 13 days late

My AF was suppose to come down on the first which is every thirty days which is normal for me, but about a week before it came down I had a day and a half of light spotting and it was pale pink not even worth using a panty liner. I thought nothing of it, so I started cramping about four days later and I got ready for my period nothing which sometimes it's off a few days. Well, after five days I started having discharge like I was ovulating and it only last two days. I knew that wasn't possible because I had ovulated already and it's always seven days not two because I always track it. Now I have sore breast, my nose is sensitivite to everything, I eat more, I'm tired more than usual (I work graveyard), I'm having lower back pains, I'm extremely gas, and I'm nausea. I took a pregnancy test  four days after my missed period and it came back BFN. I took another one Sunday and same results. Last time I was pregnant everything was the same only thing was my BFP I got after taking on day four of my missed period. So now I don't know, and I haven't told my husband yet. Can I still be pregnant have anyone ever experience this before? Also have a doctors appointment with my OBGYN Tuesday. Thanks in advance!