What might this pain be?

I have gone to a podiatrist and will go to my internist when I get home. For about a month, when I wake up, I have severe pain in my inner right ankle and it hurts to put weight on it. As soon as I walk a bit the pain eases. It hurts occasionally through the day but not as much as in the morning – which is what puzzles me. Doesn’t matter what shoes I wear. I do have flat feet and pronated ankles. I wear orthotics most of the time.