"High" can be used to a refer to a *mental state*, usually a euphoric one. Historically this was mainly used to refer an *induced* state of euphoria from drugs, but it is increasingly used to describe other natural states of happiness (eg "*I'm on a high*").

> "She's got you high and you don't even know yet"

It is impossible for anyone but the songwriter to say authoritatively what the song lyrics mean, but it seems to me that the song is about someone in relationship with a girl who is making them very happy. The girl may love the person, or they may even be *in* love but either the person doesn't realise it or is in denial.

"She's got you high" means that the unnamed girl has made the person euphorically happy, maybe that they are even in love; and "*You don't even know yet*" implies that the person has not yet realised they may be in love, or perhaps just what a good thing this relationship is.

Other lyrics from the song that support this interpretation:

> You can't deny you're looking for the sunset

Perhaps this means metaphorically that the person is looking for something beautiful? Again there is a suggestion of being in denial.

> It's the search for the time before it leaves without you

Suggesting that if the person doesn't realise this girl is a good thing and respond, she will move on.

> What's this about? I figured love would shine through

The writer is saying that love should be obvious, but the person hasn't realised it.

> Open your mind, believe it's going to come to

Telling the person in the song that they may be in denial that love will ever come their way, but that this is "closed minded" thinking.