Hi, My 3 Year Old Daughter Had A Endoscopy Last

Hi, my 3 year old daughter had a endoscopy last Friday & ever since the test she's had a sore throat & terrible cough especially at night & coughs so much she gags or gasps for air at the end of the cough. I took her to her ped & she said it was probably just from the scope test & she didn't hear any wheezing in her lungs but I had heard some on her left side on her back so the ped went ahead & gave us albuterol to use. My daughter wakes up around 2-2:30 every night coughing really bad now today I noticed the back of her throat was yellow on the roof of her mouth. Is this possibility from the scope test or some other illness & should I take her back to the dr?