Two weeks ago I twisted my ankle while hiking on vacation in southern Africa (in Lesotho). I thought it was just a sprain, didn't really feel any pain, and could walk on it. I had it briefly examined at the medical clinic at the airport the next day, got cream and pills from the pharmacy, and continued with my vacation. A week later, it was worse and I went to the emergency room in Johannesburg, South Africa, to check it out. I was admitted and had to have surgery the next morning. Now, I'm rehabbing back home for the summer.
Lessons learned/tips: Make sure to always have good insurance when you travel for accidents/events you have no control over (luckily I did), and get injuries thoroughly checked out ASAP in case they're more serious than you think. Had I done that, I might have been able to avoid the surgery.