Flector isn't going to help much with plantar fasciitis. The only two things that really help are stretching exercises (basically for the rest of your life) and special silicone heel cups (the brand is Bauerfeind and you can get them on amazon - select Health and Beauty section, then enter silicone heel cups). Mine always comes back within about three weeks of slacking off or quitting my exercises, so keep at it.

Plantar fasciitis has nothing to do with tendons - if it did, your doc would be crazy for giving you cortisone shots because they are absolutely verboten for tendon problems (they can cause the tendon to rupture). Plantar fasciitis is an inflammation/shortening of the fascia.

If the patch won't stay on, try sports tape (stretchy and only sticks to itself) or netting. Don't get it wet.