Yes, confront her...
From Create Your Own Story
You respond to her text by saying "Yes, But why do you ask? And why do you seem anxious?" She says "LOL I'm not anxious I'm stoked! A trip to the lake just the 2 of us sounds like some good fun!"
The way she said good fun still has you on edge. So you decide to blatantly ask her. "Good Fun huh? How so?" She responds with "Don't worry about it, Its not a big deal :)". Though you're still nervous the thought of getting away before college sounds like relaxing. You finish packing everything. And get into your 1985 VW Cabrio and drive to pick up your friend to head to the lake.
The two of you are blasting tunes and having a good time. When you need to get gas.