I am sure that someone will be able to help you with the antibiotics question, but just wanted to share experience of a c-section scar. I had 2 sections and found that the wound does take quite a while to heal. I still had a little bit of scabbing at the ends for a couple of years afterwards. It will still be painful for a while, you then get a bit of ache/pulling as the scar tightens. Remember, there are a number of layers of tissue that have been cut through, it's not just a surface wound. Given your experience with the infection, I am sure that you will be quite anxious, that's understandable. Just trust your judgement and in particular I think that it is burning pain that you need to watch for and just keep it as clean as you can. Your midwife/health visitor should be able to check it for you as well as the doctor.