how would you figure up your fertile and ovulations days if your period is irregular and if your period changes every month my period started 14th-20th may then the 22nd and 23rd may i had sex before the bleeding started because the app told me i was fertile then i had a little bleeding that started 23rd-25th may. here are some months when i had a period ill post . just need help figuring this up . my periods use to be normal before i had my 1st child