Allergies in a 1 year old?

My daughter just turned one on July 20. She has been really congested so I took her to the doctor for her one year check up and he said it is not in her chest it is in the back of her throat. He stated that she just had allergies. She has now gotten to the point that she coughs to the point she is gagging. While sleeping at night she was sleeping through the night and now she wakes up every hour from 1:00 to 4:30. This morning I put vick vapor rub on her chest and put her in her vibrator seat and she sleep for three hours with out coughing. We have scheduled her another doctor's appointment tomorrow. I'm just wondering does this sound like allergies or something else.