Milk supply gone?

Sophia🍦 • 👪 One rainbow sugar prince. Expecting #2 in May 2020🙏🏻

I woke up to feed baby this morning and there was noooooo swallows. I can usually hear but there was nothing today. He kept sucking and sucking til he got too tired and fell asleep. Why is this happening?

And he just lost some weight recently due to diarrhea and vomiting. Im so worried