One side ear pain while burping. Doctor.

My daughter is 5 years old. She has had cold cough phlegm for the last 2 weeks. We have treated her with azithral and she's much better now. After 2 weeks, she still has a bit of phlegm and cough but not very bad. She was also on brozedex for 5 days and is on montair lc for a month. She still has a nasal voice and her eyes Itch once in a while cos of cold. Today she complained of pain in right ear. The ears clean as I consulted drug ent a week back. I also checked. She tells me that he eat hurts while she burps or there's loud noise. It's just started this evening. She's not on any meds except montair lc. Feels like a sinus since she is also sounding Nadal but not sure. Pl advice. All meds were given after consultation with her pediatrician only. I'm worried. Please help. What can I do to help her. When should I take her to a doctor. Thank you