How Do I Know If I Need Anti Biotics? I

How do I know if I need anti biotics? I have had a terrible cough which started on Christmas Eve, slowly developing into a paroxysmic ?? Cough, then my nose started and developed into a heavy cold. Not sleeping, headaches etc. I am still coughing but not as much and I have cold sores around my nose area and all the way up my nostrils which are very painful.

I have been taking Covenia cough mixture and Benylin, also Beechams cold and flu capsules. Do I hang on or check with a Dr. I am away from home at the moment and don't return until 13 January.

Thank you for your advice.