Spotting

My husband and I had unprotected sex the day before my ovulation day, and the day after. Today I woke up and was spotting, its been brown, but now it’s brown with a little red. My period isn’t due for another 7 days, today is also 7dpo. Could it be implantion, or am I starting my period? I don’t feel like my period is coming, I have no cramps. But I have been super tired, and hungry today, I eat and then feels like my stomach is empty, also been a little bit nauseous.