So I've been breast feeding and everything has been going fine until yesterday I noticed my right…

So I've been breast feeding and everything has been going fine until yesterday I noticed my right breast isn't getting firm anymore. I tried pumping after he ate breakfast and I get 2 oz from my left one and not even an oz from my right :/ I eat oatmeal and carrots every day and I constantly drink water. What else can I do to boost my milk production?