I would tell the doctor that it is a continuing problem for him and ask if he will either revisit the issue or have a specialist look at it. It could be something fairly benign, but it would be better to know what it is than to have your son feel as though you didn't listen when he hurt. Five year olds aren't able to make choices about their medical care, and it seems as though it would be better to know for sure that there was nothing wrong, than to guess that there's nothing wrong when there is something that could be worked with.
I used to see a psychiatrist (Dr. K) who did a medical rotation with a man who I ended up using for my GP (Dr. M). They were at Bellevue in NYC. A man with schizophrenia came in complaining of head pains, insisting that it was the aliens or some such thing. Dr. M ordered tests on the head. Dr K wanted to know why, since the man was clearly insane. Dr. M pointed out that often the complaints of aliens in the head or such are made because there really is something wrong with the head, and the patient just relates to it that way.
I feel very strongly that one medical/emotional condition does not automatically rule out any and all other conditions. I hope that you can put everyone's mind at ease about your son's foot by getting a definitive answer.
