I see you're currently playing Uncharted 2. You must be quaking in your boots
Seriously though, where are you in the game?
Something really SHITTY happened to me while playing:
I had a save game file at the final boss battle for ages not being able to do it on hard (I completed it on Normal). Then, just yesterday, I tried again and managed to kill Lazarovic (too lazy to check spelling) the fifth time or so. THEN, to my HORROR it still only said 'completed on normal' because I didn't create another save game file at that point (I said cancel before started playing assuming that it wouldn't matter if I beat Lazarovic).
I WAS SO FUCKING PISSED OFF.
THEN, I tried again and overwrote another save file. I managed to kill him the 3rd time or so on hard, and felt pretty good. Again the trophy didn't appear and I was a little perplexed. Then I went to chapter select and AGONIZINGLY A.L.L the chapters were only 'completed on normal'. I overwrote the important save file. Again, I assumed this couldn't happen.
So I had no choice and started playing from the beginning again. I managed to get to the part where Lazarovic's men attack the Tibetan village in the mountains.
What makes this story special is that I'm writing my final exam for Quantum Mechanics tomorrow and I spent the time playing Uncharted instead of studying. Now, the night before, I spend my time writing about it. God, when will I learn...