TTC after being on birth control

So I just stopped my birth control before my last cycle. I used the Easy@Home ovulation test and the test showed I was ovulating but now I am four days late with a negative test. I am assuming that I am not pregnant, but if I did not get a period how am I going to know when I'm ovulating? I know that periods can be delayed after coming off birth control but I'm just not sure how I'm supposed to plan for the next cycle without knowing when I could potentially be ovulating