my foot doc will only give me 2 cortisone shots ever. first one i didn't listen.. it was given (relatively pain free) and my foot felt better so i did my usual everyday things.. and work.. on my feet. went 2 steps back. second shot was 4 weeks ago. i've babied my foot as much as possible & have taken time off work, etc. feet are impt. only get one set of them. i would suggest if you go the shot route.. get the shot and stay off your foot as much as possible. i know precisely the pain you speak off & it will come back if you do not keep off the feet. i'm young.. 33, decent enough shape, was always active.. until july when my feet totally gave out on me... other measures i've taken include voltaren (anti-imflam), icing and icing and elevating, physical therapy (procedure called iontopheresis and stretching exercises), second shot, time off & another round of anti-imflams. all in all.. i feel i have gone 3 steps forward and 2 back with every intervention. but .. i guess i should be happy i have gained at least one step...
long way to go.. but geez.. do what you can to remain off the feel and let them mend.
good luck to you. :)