22 month old has croup and upper respritory infection

My son was diagnosed with this last night..well they have him ok on steroids and antibiotics to take at home.. Now he is having horrible direaha and won't drink anything..Coughing so bad he just ends up puking. Should I take him back to the ER or should I just continue to do what I am doing?. Also I have noticed he is gasping for air every once in a while...He is playing like normal..just not eating or drinking...opinions please!!