I had Plantar two years ago; the pain, at one point become so unbearable that I had to sit propped against a wall of the Louvre. The gendarmes were not pleased; they took me to the infirmary where nurse--whose English was less than my non-existent French--wanted to put me in hospital. No thanks!
Anyway, when I returned to California I went to my doctor who offered three solutions: stay off my feet for 2-3 weeks; do the exercises, some of which above, and probably be well in 6 weeks; get a cortesone injection and be done with it. I opted for door 3. The pain of the injection was so intense for about 15 seconds! I would have given up state secrets it was so bad. But within an hour I was walking pain free. I do exercises 3 times a week and have not had a reaccurance.