Positive now negative?

Hi everyone! Last night I got my BFP! My first response tests would come back faint so I decided to take a digital before bed and the digital came back positive however this morning I tested again and now it’s telling me not pregnant. Has this ever happen to any of you and you were still pregnant? My AF still has not shown and it was due yesterday. I’m worried I’m out now since the digitals are coming back negative and my first response are now lighter.