sounds like u have been on your feet constantly for yrs???I have worked on hard floors for yrs,and when i read your post it reminded me of the intense pain i felt in my foot in exactly the same location you were describing,just a few nites ago...that's the first time i have experienced that pain......most of the time i would feel pain in the arch of my foot,intermittently....or on tops of my feet,when on my feet,.for a long periods of time...but i haven't experienced your 'loss of balance'...then at other times one foot would ache constantly,and,call me nuts,it would seem to disappear when i would have a bad tooth pulled...that's when i seem to have the most foot pain...when something is going wrong with one of my teeth.....now,for the last few years,when the tops of my feet hurt upon getting up in a.m.it seems that wearing my tenny shoes instead of going barefoot,gives me some welcome relief