Breastmilk Supply

Hey ladies! Looking for tips and tricks on helping with the breastmilk supply issue! I am barely pumping enough throughout the day for bottles and sometimes I have to dip into freezer stash which is dwindling fast. I had a fever for four straight days last week and my supply took a huge dip, it has recovered some but not all the way. I am drinking a ton of water, eating a Boobie bar each day and drinking a Upspring supplement once a day. Has anyone experienced a huge drop in supply and fully recovered? How long did it take? What helped you recover your supply?