I don't understand how you have written the code for your design and you use multiplexing when you don't have a basic understanding of what it is.
I have explained many times in the previous posts that ONLY ONE ROW IS ACTIVE AT ANY GIVEN MOMENT, you can only light columns in that row.
It is not possible to light "14 leds in one column", this would mean that all 14 row are on and this is not possible when multiplexing the rows.
You can only light all the columns in the active row and for each led one output of the 74hc595 will provide 10mA.
Alex