If you have a numb or burning feeling in your feet, have your podiatrist check you for TTS - tarsal tunnel syndrome. I was mis-diagnosed the last two years with plantar fasciitis by three different podiatrists, but I always thought it might be something else since my symptoms were not classic PF symptoms. The first step out of bed didn't cause foot pain; my heels or around my heels never hurt; it felt better walking barefoot. It is a numb/tingling/dull pain all over the bottom of my feet.
It is very easy for a podiatrist to check for TTS - they simply tap your tunnel and if you feel a shooting shock down your foot, you've got it. It's my understanding that you have to have an advanced case of TTS to be able to have that test show up positive. It can be confirmed by a electro test of your plantar nerve.