Fenugreek to increase supply!

Stephanie • Naturally delivered our rainbow baby boy in July 2015 💙 and currently expecting our second due in October!
Just started taking fenugreek three times a day to increase supply but I'm confused if I continue to take it or if I stop after a certain amount of time? I am trying to build up a stash of pumped milk while I exclusively BF my son.
I'm 10wks pp and I can only pump about 4 oz at the end of the day. HELP! 
Any hints or tips?