Why is there a black line where my neck mole was excised 2 months ago? Is a stitch still in there? (photos)

I had a mole removed by excision on my neck about 2 months ago, it's still itchy and I noticed it has a black line....the one I had removed on my back doesn't have this black line. Just wondering if that's normal? A nurse removed the stitches (dr did a continuous stitch) in my neck a week after the procedure (this may sound silly) but it's not a stitch still in there is it?!