My left ankle is swollen. i'm currently on vacation and have been doing a lot of walk. could it be the problem?

Over-use syndrome: Practicing in Orlando, I have heard many such complaints from those on vacation as they walk our theme parks. Many times it is from one of the following: Not being use to such excessive exercise causing an "over-use" syndrome, or wearing flat sandals instead of good walking shoes thus the ankle is not having good support or lack of shock absorption, or sometimes a forgotten mild sprain.