Ad 2 days early & CD confusion help!

Chelsea • Thu, Feb 28 • Miscarriage warrior (x4) Mama to a beautiful baby girl born November 2020.

Been spotting for 2 days which is normal for me on the lead up to Af. I never usually start my af on a night but just before bed I got my first show of deep red. Not a lot but def the start of AF. my question is do I class today as CD1 or tomorrow when I get a constant flow. I’m so confused.