4 days of high fertility but no peak

Rusty
Hi guys. I have a 30-31 day cycle and currently on day 19 of my cycle with the 4th day of high fertility. No peak as yet. Is this possible? To make it more complicated, I'm trying to limit sex to ovulation day to try sheetlws method of swinging the odds to having a boy. Not sure what to do?! Please advise xx