From the Charlie's LP page: "Charlie honed his talents over the years, practicing and singing in the streets for money. He was doing this when he met Desmond in passing. The first time Desmond "lived this day," he did not notice Charlie, but when he relived his past after turning the fail-safe key, Desmond recognized Charlie, and told him they were both on an Island together. Charlie commented on his statement, saying "this is why we don't do drugs." ("Flashes Before Your Eyes").
On another occasion during his street performance phase, Charlie was playing when it started to rain and he hurried off the street and happened upon a woman being mugged. Charlie chased off her attacker, inspiring her to call him a "hero." This woman was Nadia, Sayid's long lost love. ("Greatest Hits")"
Are we really sure that were two different day? I mean, the fact that in both cases started raining makes me think about the possibility they were indeed the same occasion... I admit it: I don't remember perfecty the two scenes so I could easily be wrong, but... anyone of you people had the same thought? If it was so, it would mean that Charlie has different memory of the same day... intriguing.