Color and evolution of a wound ?

Looks like the wound is healing, just not as fast as it could, if the blood flow to the area were better, and the infection that appears to be going on as well. 

Hopefully this wound is due to an injury vs a wound that just spontaneously erupted, it should heal without too much trouble. Spontaneous wounds, tend to be caused by poor blood flow to the area, or infection that has gotten under several layers of skin, as this seems to have. 

If this were my leg/arm, I would have it cleaned and cultured if this wasn't a common problem for me. I'm diabetic, and have yet to get any wounds that appeared spontaneously or because of infected blisters.

So far, my ability to heal, has not been compromised. 

I hope you have been using some kind of antibiotic ointment on that wound.

It does look like it is improving - but the little red tone to the skin around the edges of it is a sign of mild infection in the wound.  You should be covering it during the day with a band-aid and antibiotic ointment and then leaving it uncovered when you sleep.

At this time, I don't see a reason to consult a doctor.  It does look like it is going to get better.

BTW - my husband is diabetic, and I have watched and treated minor skin injuries for him.