TTC coming off cerelle

5 weeks off birth control cerelle and AF has arrived. Anyone know if I’d have been likely to ovulate last month before this?! Very heavy which I guess is due to it being the first one in a long time, but according to my dates we had sexual a couple of times right when I would have been ovulating so now I’m paranoid! Or first month off birth control is it possible to not ovulate until after your first period? I know it’s only been a month but feels like it’s taken ages to start to understand my cycle again 🤦‍♀️🤦‍♀️