Pumping

Do you think my supply might be dropping. This morning when I woke up I pumped 10oz together. Then this morning at work I pumped 7-8oz. And now maybe pumped 2oz on one side and barley 1oz on the other side. I havent changed anything. I already have drank 60-70oz of water today. I still feel full and I need to pump. I’m gonna try again when I get home. Do you think it’s because my period might be coming back or what do you think?