Hang in there. Before, during my second week post-partum, staring at that same 15ml and crying more tears than the actual milk I produced. Pumping every three hours and downing supplements didn't work for me overnight either, but please breathe, because your supply can absolutely still increase! What finally turned things around for me was covering the bottles with a sock so I stopped stressing over the volume, and adding one "power pumping" session a day to mimic a cluster-feeding baby. It took about a week of consistency, but the amount slowly climbed. Every mum's timeline is different, but if you're feeling overwhelmed, I highly recommend speaking to a professional; I actually brought my struggles up during a post-natal check-up with my gynae, Dr Regina at GynaeMD Clementi, and she was incredibly reassuring and helped me get on the right track. Give your body some time, keep hydrating, and remember you are doing an amazing job!
Hey, at 2 weeks post partum that output is actually still pretty normal because you're so early on - supply typically takes a few more weeks to establish properly. The good thing is you're pumping consistently every 3 hours, which is exactly what helps build supply. I'd say give the supplements another week or two before expecting to see changes, and in the meantime might be good to check with your PD or a lactation consultant just to make sure latch and positioning are spot on, because sometimes that makes a bigger difference than we think. Most mums I know who stuck with frequent pumping did see their supply creep up gradually from week 3 onwards, so you're probably on the right track already.