It sounds like you just had a late cycle. Regardless of how regular a female is it's very normal to have an off cycle or two. I assume you're trying to get pregnant?
Well yes it would make us both extremely happy
If you're wanting a baby you need to time ovulation and have sex every other day leading up to ovulation and then 2 days after. If you have irregular cycles (or just want to pinpoint ovulation better) you can use OPK's, chart your BBT and/or observe cervical mucous.