What could this be?!

Abigail
Alright so my LMP was Dec 9-15. This morning I woke up with bleeding (light-medium) no cramping, tired, headache. Period like symptoms. 
Anyways i wasn't expecting this at all considering I am not due for a period until 9 more days. Is this normal? Did I ovulate early? We are trying for a 3 baby and I did have sex ALOT in the past 7+ days because I was "suppose" to be fertile (<a href="https://play.google.com/store/apps/details?id=com.glow.android">Glow App</a>) HELP?!