Implantation

Hi, a question for anybody who has experienced implantation bleeding & gone on to have healthy pregnancy.. How long does it last for and how soon after did you get a positive test?

I have had light spotting for 3 days, I am at 13 DPO. my AF is due but not usually light for so long like this. Done a test and BFP but would it be too early for a positive? Probably getting hopes up & just my AF.