Iui before ovulation?

Last month I had my iui scheduled for exactly 36 hours after my trigger shot and it didn’t work . Apparently I had ovulated on my own before the iui . This month they had me come in for the iui 15 hours after the trigger shot which ended up being the morning before I actually ovulated . I thought this would be timed better , I’m in the tww now and of course I’m freaking out . I just saw online somewhere where it’s best to have an iui done the day of ovulation otherwise it won’t really be as likely to work . Now I’m worried that I just failed a second time .

My question is , has anyone gotten pregnant with an iui before they actually ovulated ? Is it possible to get pregnant when the iui is done a full day before ovulation ? Any help would be appreciated, thanks ladies .