Brief Answer:
Achilles tendonitis in my opinion, needs confirmation

Detailed Answer:
Hello ma'am and welcome.

Thank you for writing to us.

I have gone through your query with diligence and would like you to know that I am here to help. Your description matches a possible Achilles tendonitis, which displays symptoms in the following manner:

+Mild pain at the back of the leg or above the heel after physical activity (especially running)
+Pain starts increasing in intensity with the absence of rest, sprinting, prolonged running, or even climbing stairs

I would recommend a visit to your doctor for more conclusive investigations like an MRI of the region, X-ray, ultrasound, etc. In the meantime, please go about complete rest and avoid all serious strenuous physical activities (Especially running) until your doctor there can confirm the diagnosis. You can also use medications like ibuprofen to help relieve any pain that becomes intolerable or bothersome

Please also feel free to write back to me for any further clarifications, I would be more than happy to help.

Best wishes.

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