Hallo!! I have written a summary of O. Henry's short story "Witches' loaves" but I'm not sure of the grammar.. .here it is... could you help... thanks

Miss Martha Meacham is a forty-year-old baker. She becomes interested in a customer of the bakers’. She thinks he is a poor artist because of his clothes, the stains of paint and what he always buys (two loaves of stale bread). One day she hangs a painting up to do as if she is interested in art to draw the attention of the artist and it works. She is sad to see how thin he is and would like to add something to the loaves of stale bread and one day she adds some butter. He comes back later very angry and insulting her. Finally her son explains her that the man is an architectural draftsman working in the same office as the son and that he has been working very hard lately to finish a very important work. The son explains that he draws his plans first with a pencil and then rubs the pencil lines with stale bread crumbs and that the butter is of course not welcome.