Period 9 days late....

So I’ve tried starting to track my cycle as far as ovulation and stuff because my SO and I are trying to conceive. I’ve always had irregular or inconsistent cycles so I know it’s gonna take a few cycles for this app to possibly find a pattern, but I’m getting a little frustrated. We did the deed about 3 weeks ago and I could maybe possibly be pregnant...or my period is just taking forever to come along this month...maybe even skipping a month. I’ve taken 2 pregnancy tests with negative results. I guess what I would like to know is if any of you have the same problem with tracking everything with irregular cycles? Have you found anything that helps you pinpoint those important ovulation times? I’m just a little lost and need some guidance. Any help will be greatly appreciated. Thanks ladies 💕