She wants to know what time it is. Simple. Not all things have meaning.
Ask her what's the matter
Answer If a girl likes you she usually will flirt with you. That's the time to ask her out.
It could be Emotion, it could be Pain, or it could be both - ask her!
do you mean to get her attracted to you well that depends on the girl
Then the answers no? That was a bit mean of her but it means she does not like you enough to want a date with you. I would not let it put you of asking another girl though when the time is right, but wait until she is on her own before you ask next time.
marry me
He likes you
They are interested in dating you.
It could mean that she is VERY shy, I would run after her and talk to her about it, probably should give her some time though, otherwise... maybe she wasn't the one.
When you ask a girl out you have to be specific on what you mean. You could mean to go on a date or to be your girlfriend. If you ask her to be your girlfriend you should probally get to know each other more but don't do it in school because it will be akward.
Understand that no answer is an answer. It's time to ask the next one out. No
You talk to her first and get to know her then ask her when the time is right.