hi, As you mentioned, you have plantar fasciitis, the pain is in the plantar fasciitis area. Now lets understand a bit of it. When there is an inflammation in the fasica of the plantaris muscle it will lead to the pain. Fasica is the layer between two muscles to avoid friction. Also, the plantaris muscle arises from the inferior part of the lateral supracondylar ridge of the femur at a position slightly superior to the origin of the lateral head of gastrocnemius. It passes posterior to the knee joint in an inferomedial direction and becomes tendinous distally to insert into the Achilles tendon. It occasionally separately inserts into the medial side of the calcaneus. Now when you perform your normal gait cycle, which is into the weight bearing state will make changes on the contraction and relaxation of the plantaris muscle as well as tendon due to the inflammation in the fascia. Also, the tension applied will be not sufficient so the muscles of the lateral aspect of the foot will bear the load-tension. This is the purely physics explanation as per the biomechanics of your muscle movements and the pain arising. What i can suggest is to take faradism under water and this will stimulate the insertion of the plantaris muscle and also the other muscles of the foot. By which when you are applying a load (while walking) will try to balance the forces acting on the muscular system, Also, the pain is controlable but you need to meet a physical therapist for it and he will help you further. On more detailed explanation i can surely assist you. With the grace of God i wish you a speedy recovery.