Ovulation help

How do you ladies “confirm” Ovulation. I swore I ovulated or was ovulating on Sunday or yesterday because of all the symptoms I was having (extremeee headache, Cramping, etc.) but I checked my temp this morning and it’s the same as yesterday and all those symptoms are also gone. I ALSO USE OPKS. I got surge Friday and Saturday mainly Saturday !! But today I feel regular and was hoping I had a rise in bbt temp this morning but it’s still the same. And opks are negative now 😞