Antibiotics

I'm on day 5 post surgery and I had to go back to the dr. I noticed that the incision was very puffy and dark red. Basically it looked terrible. The pain had returned as well. The Dr. looked at it for about 2 seconds and said "Yep, it's infected." . He was surprised that the surgeon did not have me on antibiotics from the beginning because he said the mouth area had a high rate of infection for cuts and surgical incisions. I just hope that this doesn't cause any excessive scarring because the top part of the infected tissue is noticeable as a bump on the upper part of my bottom lip. Hopefully once the infection is kicked and the swelling goes down it wil be unnoticeable. I'm interested to know how many people were prescribed antibiotics from the beginnning and if this is the norm.