My son who is 26 and healthy recently drove across country to move for work and upon arrival discovered significant swelling in both of his feet and ankles. We assumed it was from sitting for 4 days straight and weren t too concerned. He tried elevating his legs, reduce salt, and increased activity. It took about a week for the swelling to go down. Then last week he had a 3.5 hour drive for work and back after 3 days and upon arrival at home discovered the swelling again, but this time more severe and involving mid and upper legs as well. Again, he s been elevating and trying to walk, but it doesn t seem to help much. He seems too young for this. Should he be concerned?