do u know what DAY u ovulate?

So I know you're MEANT to ovulate on day 14 BUT I think I do a bit later. This is why:
Me and SO TTC on days 12,14,16 (most fertile days, right?)
So I assumed I'd already ovulated right?
Well then I got my ovulation pain ON DAY 19 (sharp one sided sting in pelvis area - supposedly on the side where egg is released) I thought hmm that doesn't seem right bc this was ALREADY HAVE MEANT TO HAPPEN ON DAY 14.. 
So we TTC on day 19 after I felt the pain AND THIS was the day that MADE US PREG.
I know this bc we did a blood test day 23 and it was negative.
Is it possible to ovulate after day 14? Bc this means my bff who's also TTC for 5 yrs now who has a 40 day cycle could be doing it on all the wrong days! I want to give her advice but wanted to ask u ladies first