1 BFP + 3 BFN means what?!

K
Help! Yesterday was supposed to be day 1 of my period, no show. Late last night I took the ept digital and it said pregnant. In the following hour I took 2 first response tests and they were negative. This morning I took one more ept digital and it came up not pregnant. 
​I still don't have my period. 3 negatives means no, right?