Milk supply-

I'm exclusively pumping, for my own reasons, and have been for 6 months. (Baby is almost 8 though.) I'm noticing my supply drop. Usually my first pump in the morning I pump 30-40mins and get 20 to 30 ounces! I pump 5 times a day and they usually are 15-20min long sessions because I wait for multiple let downs. But, In the last month I've noticed I'm only pumping about 15-20 ounces (in the morning) and the rest of the day my left side is making 4-5ounces and my right side is only making 2-3 ounces!. I haven't really increased my pumping times or added any more pump sessions. I'm kind of just waiting it out to see how it goes and if my supply decreases too much, we'll change over to formula. Does that make me bad? It is SO exhausting pumping, planning my day around pumping, having sensitive nipples 24/7, etc etc... I'm not dropping any pump sessions, I'm not changing anything. I'm just riding it out to see if my supply will stay or go.