I've done some research on common foot problems, and nothing seems to quite match my symptoms.
When I stand up, particularly when I get out of bed in the morning, I get a little zap in the ball of my foot. Sometimes in just one, sometimes in both. I wouldn't call it pain -- it just feels like a little electric zap. Maybe it's a circulation problem? After the quick zap, it's totally fine.
Some more background information that may be helpful: I am 29, have been jogging regularly for 4-5 months, and have done a lot of hiking and backpacking this summer.
I initially though it might be Morton's Neuroma, because I also occasionally get the "walking on a pebble" feeling -- particularly in the morning after sitting on the bus for 40 minutes. But I read that Neuroma usually occurs more *after* activity or pressure, and my symptoms seem to occur only when I have been at rest, then go away. Also, the "pebble" is closer to the middle of my foot.
Thanks for any help.