Pain in Foot = extra bone?? wth

I walked 25 miles last week outside on trails, streets and treadmill at home in NH. This week I am in Florida where I walked 5.4 miles on a golf course and now have pain in the metatarsal region of my foot. Hurts more at rest than when walking on it. Woke me up at 430 Am and I went out to the couch and iced the top of the foot and woke up pain free. Until I spent time on the foot again... I did fracture a metatarsal on this foot, over 35 years ago, feels same way, but at least I knew how I caused that injury. This was one just came on suddenly.

I went to an urgent care tonight thinking that I had a stress fracture. After an xray, the nurse tells me that my shoes are too tight, well, yea, they are b/c it's late afternoon and I have been on my feet today and I am here for a sore foot which is swollen. I told him no way, have had these for 2 months and have already walked over 120 miles in them, plus, they were fitted at a running store. The nurse quick read the xray and tells me that I have an extra seismoid bone in my foot on the bottom, causing the pain on top. ( the xrays will be read by a radiologist by tomorrow). I get a prescription for naproxen, told to ice the bottom of my foot by rolling it on a frozen liter bottle. ( which I don't have, since we don't drink soda).

So have you ever heard of foot pain on the top of the foot caused by an extra bone on the bottom? I will be home next week and if I still have the pain will see an ortho, but it is discouraging considering all the exercise I was doing up to this point.