Ovulation sticks

Sarah
Hi,
Just after advice really as I have no clue about ovulation. I fell pregnant with my first while on the pill, I have now been off depo 1 year and 5 months, it took me ten months to get a period and we have been ttc since. My friend suggested to try ovulation sticks as I had no clue when I was ovulating. When is the average time for ovulation??? I have tested myself since my last period just to keep an eye out, according to glow my next period is in 14 days, but I still havent had a positive result yet. I am only using cheap sticks. Im just confused as to have i missed it or should i keep checking?! Thank you everyone xxxx