I Recently Had A Surgical Repair Of My Ankle. The

I recently had a surgical repair of my ankle. The incision became infected and I took oral antibiotics. I finished the meds about 5 days ago and my doctor advised me the infection could reoccur. I broke my ankle in a motorcycle accident where I had a lot of road rash. About 5 of my abrasions were healing and when I went to sleep yesterday they all appeared normal. When I got out of the shower this afternoon several of my abrasions suddenly have become dark purple. The incision site which was previously light red now shows dark purple where every stitch was. Is it possible my blood is infected?