Glow and Eve

Katie
Im a bit confused my last period was Sep. 10 and the one before that was August 12th... glow says i should get my period on the 5th and <a href="https://play.google.com/store/apps/details?id=com.glow.android.eve">eve</a> says that 8th... should i go with the eighth considering that closer to me regular cycle?