First Response Rapid Result

I tested today and got a bfn on First Response Rapid Result. Today is the day I should start my period. I have had 4 successful pregnancies and a chemical a few months back. I totally feel pregnant and don't feel like my period will show. Am I out or is there still hope??? I was so down this morning. I've never had this issue. Usually can test on the cheapies before my period is due and get a bfp.