"What do you want to do? I want to do what you do. I'm not really tired, though." That was the best she could do. Katie wasn't the type of girl who would flat out admit to wanting to try things, even if he was her boyfriend and they were alone. She was embarrassed and nervous and shy, and though she knew she had no reason to be, it was just how it was.
Telling him she wasn't tired was the closest she was going to get to hinting at the 'or' part of the suggestions.
"We can at least lay down though, cause I feel like your arms might get numb if I keep leaning on you like this."