Bleeding at 7dpo

Emily👼13/10/18 🌈 🤱 17-11-19💙

Guys please help me understand whats happened. I normally have 37 day cycles- I'm currently 7dpo and i know this as i had a scan followed by a positive digital ovulation test. I started spotting yesterday and thought i may have implantation bleeding, i also had aches and random sore gums out of nowhere. Then this morning Ive started bleeding properly at cd 31! This is unheard of of me, all my usual symptoms of Aunt Flow like soreeee huge boobs and really paid period pains before i come on are non existent 😥 WT has happened. Please advise! Im meant to be having my progesterone blood test this afternoon! 😥😥😥