The Achilles tendon is actually a fibrous tissue that connects the calf muscle mass to the heel bone. It causes swelling and stiffness within the back in the heel. There are a selection of potential causes of pain during the heel of your foot. The commonest causes are plantar fasciitis https://www.theorthopaedicandpainpractice.com/why-does-the-back-of-my-heel-hurt/