First pp cycle super short (luteal phase)?

Hey ladies 🌸

I had my first pp period just before I hit 7w pp. I think I ovulated around cd11, which is super early for me... I’m now just 4dpo (cd15) and I think I’ve already got my period back! This is whacked!

I’m not on any hormonal contraception and haven’t had sex, so this definitely isn’t implantation bleeding. Could it be a breakthrough bleed, or have other pp mothers had similar whacked periods with super short luteal phases? Also, I’m breastfeeding...

Would love to know how normal this is so that I can assess what my body is up to these days! Thanks all 🙏🏻