Triphasic Chart?

Elaine

Fertility friend put my original O date at the 10th. Then moved it to the 16th. My cycles have been irregular in the past, so it wouldn't surprise me if O was the 10th.

If O was the 10th, today is 12dpo. If O was 16th, this is 6dpo. Why the big spike at the end? Not sick? Didn't feel too hot. Hopeful for pregnancy this month!