Good evening. Who has had a prolonged runny nose in children? We were…

Good evening. Who has had a prolonged runny nose in children? We were sick with bronchitis two and a half weeks ago. Since then, the nose doesn't clear up. We suspect we have allergies to flowering plants. But antihistamines don't work. The nose gets blocked, it runs. It's hard to lie down, and phlegm drains into the throat. A cough starts. Tomorrow we will go for a general blood test from a finger prick. After that I just don't know who to see. ENT doctor, pediatrician, allergist ?