My girlfriend kissed me in the cheek for the first time, and in school! Does this mean things got more serious?

So, we've been going out for a while now. Out of school, we hold hands, hug, snuggle and rest on one another's shoulders. After long hugs, I've kissed her on the cheek before, but she has never kissed mine, until today. It was after a hug, as I won't see her for a week. I felt like I'd melted straight after! I got all warm and fuzzy. It was just kind of out of character for her to do it in school though, as she's quite shy

Does this mean that our relationship has developed further? And are things more serious?

Thanks
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+1 y
Also, she typed "I love you" first yesterday. Usually I say it first and she says it back
My girlfriend kissed me in the cheek for the first time, and in school! Does this mean things got more serious?
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