I was at a birthday party when two of my friends caught fire. They were lighting up the birthday candles when the fire caught the helium balloons and they burst out, My friends' faces were burnt but the doctor said the burns aren't severe and it won't leave scar. But one of my friend just mentioned purple and black spots appearing on her face. Is this a sign of the skin healing? Her lips and eyes lids have swelled as well. Why is the skin darkening? Is this temporary? Please enlighten me on this. I'm really worried for them.