I have been prepping for walking the Camino in Sept. I am 56 and have been increasing my walking the last few years to get ready. My question is, I walk a trail 17 miles straight with out stopping. I have done this at least once a week for the last 3 months. My whole body feels fine, no blisters or anything, but my feet will start to hurt the last couple miles. Will taking short breaks help or does people have an opinion it's a shoe issue. It is flat as I live in SW Michigan.