Implantation bleeding or period

Hi all,

I have had four days of nausea, headaches, cramps and then today I have starting bleeding lightly. It is mostly dark red/brown blood and has only worn one pad. See picture.

I am 7 days after ovulation and period is not due until next week. If it implantation bleeding or early period?

Let me know your thoughts

Thank you! We are trying for our first baby so its all alittle unknown to us.