1 month congested and cough

My 1 month old has a little raspy cough this whole week and it happens here and there and he has been super congested but has not ever had a fever. We took him to the ER and they did x ray and it came back clear and they tested him for flu, Covid and rsv and thank god he came out negative. We took him to his 1 month check up yesterday and told the doc everything and she said he sounds good that she isn’t concerned but ever since we left the hospital when he was born he sounded congested. Any thoughts?