This is what I found
'Can I ovulate right after my period?
The answer to this is determined by how many days are in your cycle. For example, if you have a 21 day cycle ( from the beginning of one period to the beginning of another) and you bleed for 7 days, then yes, you could ovulate right after your period. This is because we know ovulation can occur 12-16 days before your next period begins, and this would put you ovulating at days 6-10 of your cycle.'
https://americanpregnancy.org/gettingpregnant/ovulationfaq.htm
Loadsa info on ovulation there