Beginning ovulating after 8 years of constant birth control

Ok you girls always have good advice so I am just wondering how long it took you to begin ovulating/getting periods regularly after constant birth control for extended periods of time? Im 28 and have been on either bc pills or Mirena IUD since I was 19. I quit taking my bc pill last month & was expecting my period on the dot but I'm 4 days late now. I've had regular unprotected sex all month. (Not TTC, but not trying not to) I've taken 3 pregnancy tests, all neg. Ill retest in a few days if my period is still MIA but I honestly think I just havent ovulated. Halp