Question.... periods due....

Royalty • Mommy of 4 ..12/10💜 5/2 💖 7/3💙 3/22💚
So my period is due the 17th of this month.... I have been checking my cm daily. Last night however my cm was that eggwhite texture and very stringy again. And it was a significant amout. Mind u I have already had my fertile week which was last week and it was the usual egg white consistency . And my cm was in that sticky/dry phase. Do any of u ladies know anything about this??