Ballpoint Drawing butterfly

Hi there,
I tried the butterfly with ballpoint. Great and helpful excersise. And actually I was quite amazed by the result :) I also used the technique with dots and lines, and what was also new to me was darkening with more lines in stead of extra pressure (however the darkest bits I still used a lot of pressure). I hope you like it. Please leave your comments so I can improve my skills. Thanks a lot, Stefan de Vries