Typical American way of greeting. I don’t think there is any emotion in this sentence, even though people say it in different tones. It’s just a nicer way to say “hi”.
How are you? I didn’t greet this way before I came to the US. But environment changes people. Now I’m doing this as well. A certain language always conveys particular values of life, and styles of expression.
So how would you reply to the question “How are you”? For me, the answer is “good”, or “great”. Some like to say “not bad”. In Chinese we have a similar expression, and it in fact means “it’s good, but I don’t want to say it”. I guess Americans are more optimistic. Maybe “not bad” is in fact “bad” here.
How’s my day? Nothing special. A quiet person does not need so much attention. She doesn’t need so much noise, either. If she needs it, she will find it herself.