The best way to stimulate supply is to latch your baby or at least try to pump every 2-3hrs, not 2-3 times a day. Our supply works on a demand and supply system.
Also, keep yourself hydrated and try to get ample rest. Fatigue and dehydration also affects supply.
I've not used the drug that your gynae gave you before. I've only used Fenugreek pills and read about other people taking sacred tea.