PERIODS.

In my <a href="https://play.google.com/store/apps/details?id=com.glow.android.eve">period calendar</a>, it says that my period will not start until Wednesday next week, it is Monday now. But when the app comes up with tips, it says that my period has finished today. I have used other apps and that app is telling me that I will start on Friday. I experienced a miscarriage and the bleeding stopped on the 31st of January. I went to my doctors today and she said that it was only a threatened miscarriage and ordered more bloods. Any ideas??