Stressing over the milk

My daughter has been ebf, I exclusively pump, and all of a sudden my supply has dropped. I've gone from pumping 7-8oz to 2-4oz. I'm so worried I won't be able to continue to supply her with BM. We've already started supplementing with formula. I just feel like a let down! I've tried lactation cookies, I drink tons of water, I eat plenty, I'm changing my pump parts this week when they arrive in the mail, I'm trying fenugreek now. Just nothing is working! Atleast I've made it 5month 😕