Need more milk

I had my baby at 27 weeks and it took about 5 days for my milk to come in. Now it has been 4 weeks and I still only get 10ML of milk. It’s not much but is this normal for having a preemie? I pump every 2-3hours, 6.5 hours in the night and power pumping once a day. I’m taking fenugreek supplements as well! Just doesn’t seem to increase. Any tips? And is this normal for it to be so slow to not have oz and oz? Thank you so much