Implantation bleeding? (No picture)

Randi • In love with my best friend. ❤ 5/26/18 👰🤵 Mama to the perfect baby boy born 11/14/19👶💙

I told myself I'd never be this person, but...here I am. 😣 had a few light brown spots in my underwear at 8DPO (according to OPKs) and some light brown once when I wiped yesterday morning (9DPO). Nothing since. I tested today at 10DPO and got a negative, would I have a BFP yet if it had been implantation bleeding or could it still be too early? I've also had the occasional light cramping very low in my abdomen the past couple days, I never cramp until day 1 or 2 of AF. Also had a sharp pain like a line from my belly button to my vagina yesterday when I stood up. Does this sound promising like IB? I feel like a desperate crazy person, but I think that's what ttc does to us.... 😣 Any ideas would be appreciated....