I've had a number of foot problems over the past 4 or so years. It started with metatarsal pain in my right foot, which kept me from hiking for most of a year as I was waiting for it to get better (which it eventually did; I switched from Spenco insoles to green Superfeet, which may or may not have had anything to do with it, but it was what the podiatrist recommended). Once that got better, I started hiking again only to develop plantar fasciitis in the left foot. This kept me off the trails for the most part for a year or so, but seems to be fine now. I am back to my Spenco insoles. Along the way I've had pain in my hip muscles; I attribute that, and probably the plantar fasciitis as well, to weakened muscles that ended up with me walking with bad form and not noticing it, slapping my feet down and moving my legs with the wrong muscles because the right ones were too weak.

So I guess what I'm trying to say is that all sorts of things can start happening when you are out of shape and try too enthusiastically to get in shape. In my case, it resulted in me having to take a lot more time off to heal, and it's not over yet! But at least I am able to get out there now and do some serious hiking again, albeit not without some aching hips.