Someone please help :(

Lela
Okay my period was supposed to start Jan 7, I was late so I took a clear blue digital and it said I was pregnant. Well today my period still has not started but I just took another test and it said I was not pregnant, so first a positive and now a negative. Someone please give me a clue to what this may mean, I have a Dr app next week I just have so many thoughts going through my head :(