Ovulation after giving birth?

Kinda terrified I could be pregnant already... I gave birth the third week of July, have been predominantly, but not exclusively breastfeeding, and got on the mini pill as soon as they’d give it to me, but I’m going on three months without a period.

Is there anyway to tell if I am ovulating, if I have, and at what point it would be appropriate to take a test. I’m not an avid test taker, I want one and done, yes or no.

Thanks so much!

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