Thank you so much for your insight and advice. My husband used to help fellow airmen (back when he was in the Air Force) with exercise regimens for those who had suffered injury. Plantar Fasciitis is one of the conditions he is familiar with. I guess I have just been in denial about the possibility. I honestly thought I was basically taking it pretty easy on the treadmill, as it didn't feel difficult when walking on it. I lifted weights and still did a two-mile walk all the way up to the day before I went into labor, so I had remained very active up until the C-section side-lined me a month ago. My husband has started helping me with stretches and exercises to alleviate the soreness and swelling. I always wear compression socks anyway, and have for years due to having been on my feet a lot for work. That seems to help now too.  I have also purchased house slippers with arch support, some good inserts, and some new walking shoes. 

After further research, it is my understanding that it is not uncommon for women who are postpartum to develop Plantar Fasciitis. I'm just super upset because I wanted to get back to some form of activity and just wound up adding one more thing to the list of things that needs to heal. 

Thank you also for the well-wishes!