What is the literal meaning of i've been on cloud nine all day

The phrase “on cloud nine” is an idiom that means a person is feeling very happy or satisfied. Example: Will was in desperate need of a job. He applied at every possible place that he could in his town, but no matter what he did, it seemed like no one wanted to hire him.

is that the whole question?

- "chilles is sad and angry because hector, the trojan leader, killed his best friend patroclus. he seems angry with himself because he didn't or protect patroclus against the trojans."