I'm really worried about my 6-year-old who has this strange cough that sounds like barking, but there's no mucus involved. It's been more than five days now, and it gets worse at night, especially when she goes to bed, and sometimes it leads to vomiting. We've been giving her Maxtra, Arsinol, and Ziprox antibiotic syrup for five days, but she's still coughing a lot with that heavy sound. I'm not sure if this could be a dry cough from asthma, or maybe croup caused by a virus or bacteria. There's no cold, just the cough. Could you help me figure out what might be causing this?