You could be suffering from Achilles tendinitis. This is an inflammation of the tissue surrounding the Achilles tendon. Running on hills or wearing shoes with rigid soles may cause the stress that leads to Achilles tendinitis.
A hairline crack in the bone can result from repeated pounding. You may not even realize it’s happening. In fact, you may need an x-ray or bone scan to diagnose a stress fracture. Unfortunately, stress fractures can be slow to heal and can worsen if not treated promptly.
If you sustain a foot or ankle injury, you should seek immediate treatment. However, you can take several steps to treat the injury until you can receive medical attention.