question about implantation bleeding?

at 9dpo i was going to bed it was very late, about 12:30 a.m I went to the restroom because i felt really bad cramps, I was sure it was AF related ...and when i checked my CM it was pink....a few more trips to the bathroom and i kept seeing PINK... i thought i was going to start my period the next morning when i woke up (even though at 10dpo i thought it was way to early), not to mention im ttc so i bust into tears, I went to bed woke up and nothing...no sign of AF...i have very bad cramps today,boobs feel heavy and tender, i am almost sure it was implantation, it is now 11dpo and i tested BFN, Im really upset, i was sure it would be positive, what else could it have been, its too coincedental to have been anything else. Im pretty hearbroken. when should i test again? i feel like it should have been positive if i actually was pregnant.