period after ovulation??

Just wondered, how many days after ovulation does your period come ?? I only ask because I normally have a 28 day cycle but last month I was 2 weeks late for af. This month I ovulated on cd14 so assumed I was back into my 28 day cycle. now I'm no af and late by he 28 day cycle but glow is telling me 7 days until my next af judging by my late one last month. hope this makes sense and any insight much appreciated.