"I am very tired." == "I am, in truth, tired."
If we stick to that, it doesn't signify how tired you are, only asserts that you are in actual reality, literally, tired.
"You don't mean your jaw literally hit the floor, you mean it figuratively hit the floor."
No. No one ever means their jaw literally hit the floor. "My jaw hit the floor" means "I was surprised". What they mean is "I was really surprised."
No one ever uses the word "figuratively" in a non-literal sense. I can't imagine a figurative use for "figuratively"