Late Ovulation. No AF. Help?

Hey ladies,

So I'm pretty confused. My app always says I ovulate on the 3rd. I always start my period the week of the 16th. The past 3 months I have started on the 16th. I randomly took an ovulation test on the 7th and it said I was at peak ovulation. I'm currently 3 days late but the pregnancy tests are coming back negative. Im 12 dpo. Any insight?