Coeurs tournants liés - turning hearts - 3D Printed by Terry Lin

This is my first try on 3D printing, and I do not know what I have done wrong. Can someone please give me some advices? Thank you very much! The value I put for print speed was the travel feedrate (15000mm/min), and my z axis travel feedrate is 3000mm/min. I did not see a infill setting while setting up the printer, so I put 0% there. I am currently using Repetier-Host for Mac with slic3r.