Low Pumping Output

eclipselova4eva

I started back to work last week. On Monday I got 7 oz TOTAL from pumping and it was from two sessions. As the week went in I only got 6 oz total from both sessions. Now today I only got 5.5 oz total and I pump for 20 min each time. What the heck is going on! My supply can't be dipping that fast can it? I am taking More Milk Plus, eating oatmeal every day and drinking a ton of water. I'm having to send some formula to the sitter to make up for what I can't pump out. I am really hoping I don't dry up yet. There really isn't any way I can add a pumping session at work and I nurse a lot when I'm home. Any suggestions?? I can't imagine 5.5 oz for two pumping sessions is normal!