Triphasic BBT... Am I pregnant?

My cycle is usually 28/29 days. I had sex the day before I ovulated and my period is due in 5 days. I noticed a spike today 9 days post ovulation in my bbt and according to Google this could be the triphasic stage of my cycle which states that 12% of woman that become pregnant experience this spoke on day 9 post ovulation has anyone experienced this and become pregnant?