I have a breakout below by bottom lip. I have had cold sore most of my life. This cluster is itchy, like cold sores, and blisters are forming. My son has, visual diagnosed, impetigo. Butbi can't tell if it's a cold sore breakout from stress do to a wedding I'm preparing for, or impetigo. It started itching before I noticed any bumps, within 4 hours I saw flesh folded bumps starting to appear. And now 8 hours later I see small blisters. How can I tell the difference because this feels,exactly like any cold sore outbreak I have had. Itching is the only symptom besides the blisters. I have been using the mupirocin since first signs. Can you help me. I have a bridal shower tomorrow and a wedding next weekend.