Help with diagnosis

I am a 28 year old female. I have been living in Denver for the past
one and a half years. After about 2 months of coming to denver, I
started having pain in both my feet after walking for sometime. The
pain is at the top of the foot in the horizontal line where the leg
meets the foot. There is no redness or swelling. I also dont see any
restricted movement.

I used to do a lot of aerobics/walking before. But now the pain starts
just after five minutes of walking. If I stop for a minute, it goes
away too.

I spent around 3 months away from denver and I never had any pain
during that time. But once I came back, it again started after a couple
of months.

Another thing to note: I do not feel any pain in case of start-stop
walking like going around in a mall since you stop a lot inbetween.

I went to a doctor last week. Waiting for the xray results but getting
anxious.

Can any of you comment on what these symptoms may represent?

Thanks
Karen