Breast milk supply almost gone

So my baby is almost 3 wks old and unfortunately my milk is not coming in like it should to satisfy baby's feeding. I am taking Fenugreek to try and help milk supply but it's not working in just pumped this morning and I only got 16ml for both boobs combined. I'm also doing formula because I need to make sure he is getting enough to eat. I want to breastfeed but feel may be at the end. Help I need advice to help milk supply?