My 2 years old G. shepherd was hit by car and after 5 days of trying to save her paw the leg was amputated due to unable to heal lost skin and deteriorating condition , 2 days after surgery the suture looked nice and normal color skin ,, now 5 days into it on one side of the suture the skin became dark almost black of about 1 inch and about 5 inches in length hardened to the touch ,,  seems like a seroma has also developed swollen tissue even testicles are bigger pinkish fluid discharge occurs but not too much only when he moves dog is in good spirit,  heats with good appetite,  poos, pees and walking ,, the dark skin around the wound is my concern.  ..

Thank you very much