Dehydration effects?

PsyDr04

I've had a stomach bug this week (finally feeling better today). While it doesn't seem to have affected the amount DS gets when nursing, I notice that I haven't been able to pump the same amount that I normally do, especially in the mornings. I read that unless you're REALLY dehydrated, your supply shouldn't be affected but has anyone else noticed a decrease in the amount you have been able to pump after a bout with the stomach flu?