My son smashed his right foot on the banister 10 days ago and it is still swollen, top and side and can't bend his pinky toe without feeling pain. Overall, he doesn't have much pain except when walking or standing for a while. He feels a lump on the sole when he stands. The middle of the sole is blue and swollen too. 

X Ray was done but nothing was shown and nurse told us off for even asking for an X Ray in the first place. She dismissed the symptoms and say that he can walk 30 minutes to uni. I am not convinced of her diagnosis. 

Could it be Lisfranc injury and should he be careful and seek treatment?