Could my 2 year old son have a more serious problem?

My son started off sounding like he was loseing his voice 2 weeks ago. Then a couple days of that he started with a 100.5 temp that also for a couple of days. From that it whent to a cough. The temp had left and his voice was ok again. But he is coughing so hard he is throwing up. He haslost 3 pounds and continues to cough and throw up. He would try and eat a little then he would cough and it would come back up. He is drinking lots of fluids but he throws those up as well when he coughs. I took him in twice. And finally last night after some blood work, swobs and an x ray the doctor came by and said it seems like R S V soon after the nurse came in and gave me papers for Bronchitis. They tested for the flu and said it was not the flu a cold or strep. Dose anyone have any thoughts???