Help.

It was a cloudy and strange day, anybody was around, anybody was walking on the street, anybody was waiting for the bus, anybody was drinking a coffee in a bar. It was just me, the wind and a bird. I remember that i was singing under a tree, when a pretty girl suddenly appears. She start talking, even that I didn't stop singing. I can't tell you most of the stuff that she said, but it isn't because I don't want to. Is just 'cause I forgot absolutly everything. If I take a while, and think, all of this come to my mind, but when I want to talk, it's gone. Just like that. Could you explain it to me? I still can't get it.