I'm literally pumping nothing!

Alexis • 3 year old Chloe💖 11/15/15 & Jacob 💙 3-5-19
I need help! And bad! I'm exclusively breastfeeding and I work part time.  For about the past week it seems as though my milk supply is going down, when I've pumped for the past few days it's literally only drops coming out. My daughter seems to be full and getting milk when she eats, which is good. The only little bit of milk I can get is at work while we are apart for a few hours I can pump about 3-4 ounces. Does anyone know what I can do to get my milk supply up? I feel really desperate to do anything for more milk now.