I had a melanoma removed my my lower leg/upper ankle the 1st of August. The cut was horizontal about 3 inches and the middle of the cut is open and not healing. After getting part of the stitches out after 3 weeks I had to be on antibiotics and then I got the othersstitches out and had to have another round of antibiotics. It had a thick scab that I took of and it wasn't healed beneath it. Still very red around it.How long should this take to heal?