What it means
The God who made everything does not get tired, and His understanding has no bottom. He is not worn down by your situation, and He is not puzzled by it.
Isaiah comforts exiles who think the LORD has overlooked them. Three verses later comes the promise that those who wait on Him will renew their strength.
Where it addresses you
You are exhausted and assume He is too.
No one seems to understand what you are carrying.