Please review with your Obstetrician as you can be easily prescribed measures/medicines to help increase your milk output: stay stress-free, increase fluid intake, take nutritious diet especially nuts:these help increase milk production & secretion.
Medicines (like Metoclopramide) can be tried
Also offer areola along with nipple (rather than just nipple) while feeding; try and feed from one breast & empty one side, than feed from both breasts, as half-empty breasts decrease milk output over time
Next Steps
Dr review, especially Obstetrician, to rule out inverted nipples, cracked nipples, reassurance
Health Tips
Try home remedies to increase milk output, remaining calm & relaxed is the most important.