When I was a resident, a woman brought her child to me and told me “there is something wrong with my child.” I asked her what was wrong and she could not explain what was wrong; she just knew that something was wrong. I examined the child and finding nothing wrong, told her so.
She knew in her heart that something was wrong and so she brought him back over and over. She saw other residents (pediatricians just learning for the first time how to be a pediatrician) and more experienced pediatricians. Each time, the examining physician was not able to identify anything wrong. Until one day, when he did have identifiable symptoms. Then we all knew that something was wrong and it was terribly wrong; he had a brain tumor.
I and the other doctors listened to that mother; we conscientiously looked for what the problem might be. We didn’t find the problem for a while.
As a parent, if you know that something is wrong, say so! And keep saying so until you are satisfied that really nothing is wrong or the thing that is wrong has been found. And if you are in the medical field, listen, listen, listen.