The setting of this story is in a small town in Spain. I believe the conflict in this story is Person VS Person, between the girl on the balcony and the young man which first seems to be unrequited love.
However, after numerous attempts, at the climax, he actually managed to be with the girl of his dream. I think one of the obvious symbols in the movie was use of colours. The screen was monochrome until the appearance of the girl, but became colourful as soon as the young man sees her. So colours could be the symbol of the girl of his dream. I suppose the ending could be a type of irony as it was quite surprising to see the man succeeding to get the girls' attention after all those comical acts. I believe main theme of this movie is Love.