I tried fenugreek, but eventually gave up and switched to formula. I was battling with my supply, tried everything even perscription meds, but by 4 months i had to switch unfortunatly as nothing really helped me.
Perhaps just give it a bit of time and see if it kicks in nicely for you
Some women claim that Fenugreek helps their supply, oats, Brewers Yeast tablets etc but the only best way to increase your supply is to feed on demand. Lots of skin to skin contact, keeping hydrated etc.
Some medication can decrease a mother's supply, introducing formula in between(because that signals to your breasts to produce less milk) because baby isn't feeding a lot on the breast. Empty breasts doesn't indicate low supply. An empty breast signals that more milk should be made. Bf babies need to drink between 10-12 times a day in the early weeks.
Can you give more info on how baby is drinking etc. How many wet & dirty nappies? Weight gain alone is not a proper indication.