spotting for 12 days with ligt pink color

last year i was diagnosed with HPV and had to have a coinization. ever since then my periods have been normal and my paps have been normal as well until know. ln June i had a extremelly light period but then in July my period was normal and then this month i began spotting 1 week before my period and i am on the BCP. I have been spotting for 12 days know the color is a ligt pink i and is only there when i wipe. i have been reading about the implantation bleeding and am not sure if what is happening is due to that or possibly some other issue.

please help