Why did my mole have discolored pigment left behind? (Photos)

I had a mole removed about 3 months ago and I had taken pictures one week after and it had pigment left behind while it was healing. I got the call and told the mole was not cancerous so i put it off, now I am seeing pigment pop up and started freaking out if this is normal from a shave biopsy or it was possible melanoma. Here are the photos from a week after the biopsy and now.