I've been trying to conceive so I recently downloaded glow.. But before glow I was using my <a href="https://play.google.com/store/apps/details?id=com.glow.android.eve">period calendar</a> and glow "says" I was suppose to start my period 4 days ago but I didn't.. And my <a href="https://play.google.com/store/apps/details?id=com.glow.android.eve">period calendar</a> "says" my period suppose to start today ! But it hasn't yet .. What should I do ??