Ok so I was sharpening some knives at work and i cut my index finger. It was a sharp knife so it sliced my skin like almost filleting it but not cutting it off. its a decent cut but not something that wouldnt stop bleeding or anything. I cleaned it with hydrogen peroxide and put a band aid on it and it stopped bleeding after about 15 mins. Now is it ok if under the skin theres a black and blue line that i dont know what it is. I was sharpening a knife so there might be trace amounts of metal in there so i dont know if thats somthing to worry about. Any one have any suggestions?