Describe something valuable that you lost

Last year I lost my phone, which was probably the most stressful thing that happened to me in months. It was a fairly new model that my parents had given me for my eighteenth birthday, and it contained all my photos, contacts and study notes.

I lost it on a crowded minibus on my way home from university. It was a Friday evening, and I was exhausted, so I put the phone in my jacket pocket and fell half asleep. When I arrived home, I put my hand in my pocket to take it out, and it was gone. At first, I could not believe it. I turned my bag upside down, then ran back to the bus stop, hoping to see the same bus, but of course it had left. I called my number from my sister's phone, and for a while nobody answered, which made me more nervous. I also used a tracking application to see where the phone was, and it showed a location on the other side of the city. Finally, around eleven o'clock, a man answered and said that he had found it under a seat. We agreed to meet the next morning, and I got it back, undamaged.

I felt terrible for those few hours. I was upset about the money, but even more about the memories and data I might have lost, as I hadn't made a backup in months. I was also embarrassed about my carelessness. After that, I changed some habits. Now I always keep my phone in an inside pocket and I back up my files every week.