Try latching baby on as much as possible? I struggled with my son as well because he was given bottles in the early days due to jaundice and low blood sugar. He was very fussy at the breast for weeks so in the end I said no more bottles and just latched him on directly. Every time he cried and kicked I calmed him and tried again. We got there eventually, now he feeds like a pro.
You can always try expressing after feeds for a couple of days to try to increase supply. Also offer the breast as much as possible, you can offer a topup feed 40 mins after feeding and see how he takes it or increase the number of feeds to two hourly. The more milk that is removed, the more milk you will make.
Foods like oats, linseed meal and brewers yeast are great for increasing supply...but then again they dont't work for everyone which is the same with fenugreek.
Rest as much as possible and dont't stress! Hope it all goes well