Faint positive disappears while breastfeeding.

I am 7 months postpartum and exclusively breastfeeding, at 6 months I got ovulation cramping followed by implantation spotting a week later and then 2 days later got faint positive, it’s stayed the same for two days and then line disappeared. I’m assuming it was a chemical pregnancy, but the weird thing is I never got my period since birth and also nothing after all this. It’s been over a month so I’d think I should have a period since I ovulated. Has this happened to anyone?