Unfortunately, I don't have any information that could help you. I just wanted to say that until you know more,
try not to panic. I know that's easier said than done though. It's nerve-wracking and heartbreaking whenever a pet is sick, since they can't tell you what's wrong and you don't know how to help. You feel so worried and helpless. But it could be something that is easily treatable. Try to think in those terms. I think at this point, trying to do any more research on your own is just going to make you panic and stress out more. You'd just be spinning your wheels. The only way you will know for sure what's going on is when the vet can take him in and do a lab test to check for any possible infections. I think trying to diagnosis the problem yourself is just going to cause you more stress.
Ask the vet what you should do in the mean time, and then do your best to keep Jake comfortable until he can be treated. That's really all you can do.
And remember too that sometimes things might seem worse than they actually are. I remember a while back, Chipper had stuff on her feathers all around her beak, like she had been throwing up during the night. She also seemed a little bit less active. I panicked and immediately set up an appointment to take her in to the vet. I was so scared that something was seriously wrong and I was almost crying. She started doing better throughout the next day, she was eating and playing with her toys. But I was still really worried. I took her to the vet and they took a culture from her mouth for a lab test. The doctor said she looked fine, but thought a lab test was a good idea to be on the safe side. It turned out there was nothing unusual, and no pathogens, thank God. Within a couple of days later, Chipper was perfectly fine. I still don't know exactly what happened, but it's possible that she just ate something that upset her stomach a little. She's never been sick since then.
I know undigested seeds in the droppings is a more serious sign, but try to keep in mind that it might not be something too serious and could be easily treated.
I hope your birdie will be feeling better soon. I'll pray for you and Jake.
