How late did you get your BFP after implantation bleeding?

Hi everyone! I believe I had implantation bleeding on CD 27 and 28 with some spotting either side of it, a couple of days before my expected period. Since then I've had quite a few but very mild symptoms. I'm now on CD 33 (if the bleeding wasn't my period) but tests come back negative. Could it take longer to get a positive result after implantation bleeding for some pregnancies? Like a week or more after implantation? I swear I'm feeling some pinching / pulling in my lower left abdomen and can't imagine why that would be several days after a period. Thanks!