Had/have secondary infertility

My first is 10 years old & i couldn’t get pregnant since having her, (secondary infertility), so i underwent fertility treatments to get pregnant with my second which is now 5 months, i started getting my periods again at 4 months pp, & currently on day 3 of my new cycle. A little background story, i always had my period every 30 days, i just wasn’t ovulating. I had anovulatory periods basically. Sooo, i wanna start tracking my ovulation & see if i can ovulate now or will i have to go through the process again to conceive again. (My first child came natural) But i honestly dk how. I got this ovulation/hcg set thing of amazon but idk when i should start. Any advice? Does anyone know if secondary infertility remains? Thank you ladies.