From the symptoms you are describing, it sounds like you may have something called plantar fasciitis, one of the most common causes of heel pain.
The plantar fascia is a band of fibrous tissue that attaches to the heel and the divides and separates to attach to the toes.
It can become inflamed for reasons that are not well understood. It is thought that prolonged standing, being overweight, flat feet and heel spurs may contribute to the development of the condition.
When you are sitting or sleeping, the band of tissue tightens because your feet are in the relaxed position. Then, when you stand up, the tissue stretches and this causes pain.
Initial treatment begins with anti-inflammatories (aleve or ibuprofen) and icing the foot.
Wearing heel inserts or arch supports may also be helpful for you.
When you first get out of bed in the morning, have a supportive shoe or sandal to step into. Avoid going barefoot.
If these things do not help, steroid injections into the foot are helpful. Thus, a doctor visit would be warranted at that point if the above measures are not working.
Here is some more information for you about the condition.
Feel free to ask any follow up questions you may have.
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