Awesome info. Thanks everyone for your contribution.
I've been trying to follow as many of your advices as possible. Amazingly, after knowing the term, the stuffs I researched and your info, things seem to be better. I got two new pairs of shoes with laces, put away all my laceless shoes, and been stretching and skipping tennis (the hardest part). The morning pain has reduced substantially.
Walking barefoot, which someone suggests, on cold tile floor is uncomfortable though. I walk around the house in a soft flip flop. But I think the suggestion to walk on a beach or grass makes a lot of sense.
Povl Carstensen, how do you make "homemade J-shaped heel insert"?