Hi Anshul,
As Saisenthil suggested, you should not store lactogen milk for longer.
Think positive about breastfeeding...'coz they say the lactation depends on how you think. Normally most mothers get to feel the lack of sufficient milk for their babies after the 3rd month. At this point, your baby's proper growth is more important than you feeling guilty. Relax and feel good that you are doing something in the well being of the baby. I'm sure your lactation will also improve if you think positively.
Additionally, you can post this query here
Parenting-Breastfeeding.
My My 2cents,
Hema