Quick question regarding ovulation

Samantha • I`m 31 ttc # 3, we have a 9yr girl and a 15 month boy. We lost our little girl in April at 16 weeks.
So I took an ovulation test and it was positive on 8/5 so now that it is 8/15 how many dpo am I? Do I count from the 5th or do I add a day or two since ovulation happenes  after you get a positive? Thanks!!