I Was Bitten By A Dog 10/23/16 And Received 11

I was bitten by a dog 10/23/16 and received 11 stitches on my right hand . Part of the area was really mangled. Now 10/29/16 part of the mangled area has turned black. It's cold and has no feeling. I have and appointment 11/02/16. Should I go to the ER? I can provide photos if necessary.