Need some help on this one.

Ash
Okay I got my positive peak opk on the 14th of August. I tested the following day with a wondfo and it was even darker on the 15th. I know that's they only detect a surge so I'm trying to figure out when I actually ovulated and what dpo I am. I don't temp either. Glow says af is suppose to be here today. As of right now I feel fine. My other app says I have three days before I start my next Cycle. Yesterday afternoon I had light brown discharge in my underwear. It was enough to be like "whoa". I assumed my period would be coming. It was only when I wiped. On and off for about 4-5 hours. I just never had any cramps with it which was odd. If I ovulated 1-2 days after my positive opk that would only make me yesterday 10-11dpo. Instead of glow saying I'm 14-15 dpo. If this has happened to someone please let me know. Appreciate it