When the hell am I going to ovulate?

Some background information: I'm about to turn 26, husband is 34 and we'd like to try starting for a baby in October. I was previously on Nora Be (progesterone only Birth control) for a little over a year and stopped on July 2nd. August 8th was Mt first period without Birth control. I had a peak on CD 17 but it doesn't look like I've ovulated... Now my OPK say "low". When am I going to ovulate? This is so frustrating!