Implantation question

Shannon

AF is due to come on the 22nd. Last night I had some mild cramping on one side and this morning it was pink and some actual spots. Then a few hours later it's gone, like it never happened. How late in the game can you have implantation bleeding? I'm 10 DPO today according to glow. AF would be showing on 14 dpo. I took a test yesterday and it was negative.