Am I losing milk???

Ye

I have a 3 month old and exclusively pump. This whole week I have not been pumping as much milk like I normally do. I pump every 4 hours and nothing has changed in my diet. Is there anything that could have affected my milk that I’m doing? I’m working out a little more in the gym....that’s about it. Is this normal? I usually pump 10oz and I barely get 6oz from both boobs.