Foot pain upon standing

I am a 61 yr. male who is 5’11”, weigh approx. 210 Lbs. While off my feet I have no pain, but upon waking and standig beside the bed I nearly fall over from pain on the bottoms of both feet until I have walked (hobbled) for a while. After walking around some the pain subsides. Later in the day the pain recurs and is continuous until sitting or lying down. Upon standing again the pain again recurs. My feet are now taped by a podiatrist for 4 days. Upon removal and a week’s followup visit he wants to know my symptoms. He tells me to stay off my feet as much as possible, which I am attempting to do. The taping has help quite a bit, but I now have pain while my feet are elevated (with the taping on). What sounds to you to be the problem and therapy?
Thanks,Pascal Allison