not getting enough colostrum anymore?

i had an emergency c section, my daughter is in the nicu so i've been pumping since friday. i've been pumping out a good amount of colostrum since she was born about 45 ml was my highest in the tube. but today i've noticed i'm barley getting anything out! i'm starting to freak out cause my baby girl needs it due to her being in the nicu. i do pump every 3 hours. could it be stress? i do drink a lot of water, i've tried massaging my breasts as well. any recommendations ? it's been week since i've had her i'm not sure when my actual milk is suppose to come in.

TIA ♥️