After getting back to work , you may get more milk than when you're at home. Because you don't feed for almost 4-5 hours before pumping.
Try to empty your breast as much as you can so that your body can generate more milk. Also, I tried to pump at midnight to save more stocks. You'll feel less stressful when pumping at work. Or if your bb allows, pump and feed at the same time,e.g., using manual pump.
Hope you enjoy BF. Any pbms, let us know. I had gone through many problems, too . So, don't be upset. Everybody is the same as breasfeeding mother. We can give you some advices because we had difficult time too.